In "Stuck In Ed", Eddy does a scam involving getting the cul-de-sac kids to submit their ideas of a scam to the Eds, Jimmy gives them an idea, Jimmy's scam involves 10 extension cords, 10 refrigerators, 100 fenceposts, various fruits and many gallons of water, it turns out that Jimmy's idea for a scam involves Ice Pops. You'd think: That even for as childish a scam as it is, Eddy would see potential and use Jimmy's scam in the future. Instead: Being Eddy, he angrily rejects the scam. Result: The Eds don't get a buck the next time they cook up a scam., Great going, Eddy.
At one point, the Eds literally get stuck inside Johnny's wall, presumably to avoid the Kankers, and need a way to get out. You'd Expect: The Eds, particularly Ed and Eddy, frequently showing abnormal physical strength, to break through the walls no problems. Instead: They waste time by making up stories and eventually get attacked by the Kankers (who aren't really 200 feet tall) again.
Double D is handed what appears to be a can of jelly beans. Double D is standing in an abandoned factory originally used for pranking toys, with two guys known for pulling pranks; in fact, Double D had just been pranked by the other two Eds into believing they had been killed by a supernatural figure. Also, the Eds are on the run from the kids, and can't afford to attract any attention to their position. Finally, we're talking about a guy who actively lampshades his being Surrounded by Idiots on a regular basis. You'd Expect: Double D would suspect that Ed's follow-up offer, quite possibly thought up by Eddy, for a can of jelly beans was a trick. After all, "fool me once, shame on you, but fool me twice, shame on me". Instead: He just accepts the offer, not suspecting anything at all during the whole minute he tries opening the can. The result? The can causes an explosion of many rubber snakes being spewed all around the factory's area. Kevin, who was in the area with Nazz, realized where the Eds were hiding, although this didn't help them all that much in catching the Eds, since they move on anyway. Of course, Double D himself was propelled by the explosion, and ended up stuck to a rock high up on a waterfall.
In "Brother, Can You Spare an Ed?" Sarah entrusts Ed with her money to buy her and Jimmy some fudge at the candy store. Eddy, the greedy jerk he is, wants Ed to buy jawbreakers, but Edd insists that it is Sarah's money, so it should be spent to her specifications. You'd Expect: One of them should realize the threat Sarah poses if her for once reasonable request is not met. Instead: Edd and Eddy argue over the proper usage of the money, representing integrity vs. Greed, respectively, until impressionable Ed enters the store and gives into temptation, only remembering that Sarah intends on kicking their asses when it is too late. Well, we would not have a show if they did not get into these jams. But then again: Sarah shouldn't have entrusted Ed to do the deed, knowing very well about his stupidity and Eddy's greed. Instead she should have asked someone else to buy the fudge, or go buy it herself.
Similarly, there occasionally comes times for when the Eds will need something that no one else seems to have/will be able to get/give them. Unfortunately, one of them will get the idea to go to the Kanker Sisters. You'd Expect: The Eds would be wise enough to avoid the girls that borderline sexually harass them every chance they get. Instead: They go right for the Kankers and end up with the same old ending of getting Covered in Kisses or otherwise.
Inverted in "Once Bitten, Twice Ed": Eddy comes up with a "follow the talking mailbox to a shoot the raccoon game"-scam. At first it seems to work, but then Johnny shoots it down for animal abuse and Eddy is forced to give a refund. You'd Expect: Eddy to give up and find a better scam. Instead: He concludes that the raccoon was the problem, and despite both of the other Edds given up, he spends the whole day coming up with expies. He only got costumers twice and didn't earn anything at all (Sarah even caught on)
Within another infamous episode known as "Your Ed Here", Kevin discovers Eddy's Embarrassing Middle Name and uses it to blackmail him. You'd Expect: Eddy to tell Double D and Ed or his parents about the situation, especially since Double D being DoubleD and Ed being Ed, they would understand. Or even better: Know better to not let Kevin blackmail him (because trusting an enemy of yours to keep a secret won't be smart) and learn to accept his middle name and not care if anyone makes fun of him for it. Instead: He keeps it a secret to himself and lets them know at the last minute after Kevin humiliates him. Thus: Kevin doesn't get punished for what he's done.
Also, in the infamous episode "If It Smells Like An Ed," Jimmy confessed that he was the one who framed the Eds after Eddy humiliated him by giving him a wedgie. You would have expected: For Jimmy to target Eddy only because Eddy alone humiliated him. Instead: Jimmy targets Ed and Edd along with Eddy. I mean, why target two people who didn't do it?
Before that, the Eds invade the kids' Friendship Day, Jimmy offers to befriend them. You'd Expect: Eddy to get along with Jimmy and potentially the other kids and gets what he wanted; respect from his peers. Instead: His jerkass tendencies kicked in once more, he bullies Jimmy by wedging him in front of the other kids, thus causing Jimmy to do the above Evil Plan and the Eds end up humiliated. Freudian Excuse or not, Eddy really needs to lighten up.
Also, as mentioned above Eddy wrongly humiliates Jimmy by wedging him in front of everyone. You'd Expect: The kids or even Edd to attack Eddy or at least call him out for it. Instead: They all just stand there and laugh at his expense. Sarah has to step in to get them to stop.
In the episode, the Eds try to find out who the person framing them is. The method they have is getting everyone to put their foot on a large footprint (that ended up being Jimmy). This works up to comedic effects, but when they find Jimmy himself, they find him with a hockey stick. Eddy gets angry. You'd Expect: One of the Eds to grab the hockey stick (which had black tape wrapped around it) and unwrap it, finding out that he was the culprit sooner. Instead: They ignore the hockey stick and just put Jimmy's foot in there, thus fueling some more anger in Jimmy.
Jimmy also captures Jonny and makes it look like the Eds did it (by turning him into a "Giant Jonny Chew" scam wrapped around with candy). You'd Expect: The Eds to untie Jonny, as this suspicious activity makes it look like the Eds made a scam to get the kids even more upset. That way, the Eds could ask Jonny about the whole scam. Instead: Eddy spends some time joking about the scam and Ed eats the candy around Jonny. Eddy also tries to measure the footprint against Jonny's foot. By the time the kids come, they are already upset from earlier, and they chase the Eds.
What's Worse: Jonny for some reason chases the Eds as well.
During the climax of "Mirror, Mirror on the Ed", Eddy (who is currently dressed up as and forced to act like Ed) has to hide in Edd's house because of pissed off Kevin wanting to beat him up after Eddy teased him. Suddenly, the alarm in Edd's room activates for no apparent reason. You'd Expect: Edd, being The Smart Guy, constructing the alarm in a way that locks the burglar in or recognizes one of his friends. Instead: The alarm opens the door, allowing the potential burglar to escape, and Kevin to beat up Eddy.
The Eds and Kankers were in a "squirt-gun duel" and the Eds aren't landing any successful shots at them. You'd Expect: The Eds to realize they're wasting ammo and pull themselves together. Instead: They fired wildly, used up all their ammo, the Kankers remained unscathed, they incapacitate them by using a special sticky substance and the Eds endure yet another sexual attack from the Kankers.
In "Ed Overboard", Ed gets kidnapped by the Kankers and Edd and Eddy agree to let the Urban Rangers save him. At one point, Johnny and Jimmy are trying to untie Ed from a tree as Rolf distracts the Kankers, but then Ed yells and they tell him they won't help him if he isn't quiet. You'd expect: that Ed doesn't say anything and has Johnny and Jimmy save him. Instead: Ed decides that he should call for help even though they're trying to help him, and he yells out "London Bridge", thus making the Kankers catch them. Granted, this isEd we're talking about here.
Throughout the series, it's hinted many a time that Eddy's brother is a monster instead of the Cool Big Bro that he often says that he is. For example, one of his inventions is a gigantic stink bomb, he sends Eddy baby toys and apparently he did something to Rolf's chickens. You'd Expect: That the other kids and Double D and Ed would catch on eventually. Instead: Eddy does everything to hide his brother's true nature, and we don't learn the truth until the movie.
In "Avast Ye Eds," when the Eds are in their tire float, the Kankers launch a bobby pin on it and the pin gets stuck. Eddy walks over to the spot and Edd tells him not to pull it. You'd Expect: For Eddy to listen to Edd and not to try to pull the bobby pin off. Instead: He foolishly pulls the bobby pin off, causing the float to deflate and the gang to land in the water and the Kanker Sisters to kidnap them on their boat. Then: Jonny and Jimmy are forced to walk the "Plank", and the Eds end up getting raped again. Happy ending, indeed.
In "Little Ed Blue", Ed has gotten cranky and Eddy and Edd (well, mostly Edd) try to help him. They then spot Kevin pitching baseballs at Ed's head. You'd Expect: Kevin to leave Ed alone knowing that he could crush him. Instead: He (along with Eddy no less) keeps on annoying Ed. The Result: Ed forcefully morphs Eddy into a baseball bat and whacks Kevin with it.
In the episode "Smile For The Ed," Eddy wants to take a good picture of himself to show to his mother. However, Kevin ruins Eddy's picture by calling him a dork while he poses for it, and the picture ends up looking horrible. You'd Expect: For Eddy to just report Kevin's bullying to the principal, to insure that Eddy can retake his picture without Kevin interfering. Instead: The Eds attempt to retake the photo and Edd ends up impersonating the principal, which ends in chaos and with the Eds getting detention, while Kevingets off scot-free However: Since Adults Are Useless, it's likely that Failure Is the Only Option.
In "Truth or Ed", Eddy gives himself a false identity (Bobby Blabby) to create lies about the kids. But Ed soon accidentally makes him confess the truth. You'd Expect: Eddy to keep his mouth shut when Ed mispronounced his false name. Instead: Eddy blurts out his secret in front of the kids, thus blowing his own cover. The Result: Knowing who Bobby Blabby really was, the kids punish Eddy by having him knit the world's largest doily.
In "Here's Mud in Your Ed", Rolf and Jimmy fool Eddy into believing simple objects are money tree seeds. So he gives up all his possessions in trade. And he falls for it twice. You'd Expect: Eddy to realize he's been played the second time around. Then again, he shouldn't have fallen for it the first time since there's no such thing as a money tree. Instead: After angrilly consulting Rolf for conning him, he falls for it a second time. Ed himself replies "Even I am not that dumb, Double D".
In the episode "All Eds Are Off", the Eds, Rolf, Kevin, and Jonny take part in a bet, with the cash prize of $1.25 given to the person who can give up on an annoying habit of theirs the longest. Eddy (of course) attempts to cheat by getting the others out by tempting them. He starts off with Kevin, who has to give up on calling the Eds "dorks" You'd Expect: For Kevin to see what Eddy is trying to do, and find another word to call him besides "dork." Instead: Kevin gives into Eddy's taunting and starts shouting the word "dork" repeatedly. Thus: Kevin loses the bet.
Also, Eddy's next target to tempt is Edd. Edd has to stop using big words and can only form sentences with 4 syllables. Eddy tempts Edd by tearing out pages from a dictionary. You'd Expect: For Edd to make up a sentence with 4 syllables to get the book from Eddy, or matter fact, just snatch the book from Eddy without saying a word. Instead: He gives into temptation and starts using big words, thus losing the bet.
At the very end, when Ed jumps into a gravy-like liquid and appears to lose the bet, Eddy is happy and wants to rejoice. You'd Expect: For Eddy to read the label of the can to assure that it's gravy, to make sure Ed really lost the bet. Instead: Eddy starts to celebrate that he won the bet, and starts shouting really loud. However: When it's discovered that the "gravy" that Ed jumped into was in fact butterscotch, Eddy gets upset and then puts his hand over his mouth, realizing he lost the bet.
The episode "Too Smart for His Own Ed" just clarifies how dumb the characters are, following Edd's mistake in a spelling bee. You'd Expect: The kids would have treated Edd the same way despite getting one word wrong. Instead: Just for misspelling the word "Gravy" by one letter, everyone treats him like an idiot, preferring to have Ed help them with a test.
The episode "A Twist of Ed" has Ed and Edd to use reverse psychology to end the Kankers into harassing them once and for all. You'd Expect: Eddy would join in immediately to get his revenge on the Kankers. Instead: He spent the whole time cowering, believing it wouldn't work. By the time Eddy decided to join in, Lee figured it out, and the result was a complete disaster. Good going Eddy...
In "Out with the Old, in with the Ed", on the last day of summer, Double D tells everyone school will start tomorrow. Since Double D is the only one who thought ahead about school, he has bought back to school supplies. Everyone else realizes they forgot to buy back to school supplies, and thus steal them from Double D. However, Double D soon realizes that Ed has a back to school sale coupon from his parents, and begs him if he could help him buy new school supplies with it, which Ed is happy to do. You'd Expect: Double D to go into the store with Ed and supervise him to make sure he buys him every back to school supply he needs. Instead: Double D, confident that Ed will buy him every back to school supply he needs, waits outside the store until Ed is finished shopping. Instead of buying Double D the back to school supplies, Ed has bought him a bag of pancake mix, a urinal, a stepladder, and one pencil (the last of which he has already chewed holes in).
"Dim Lit Ed", an episode that actually uses this trope as its basis, has a pretty good one: Double D decides to hold a scavenger hunt in attempt to sharpen the deteriorating minds of the Cul-De-Sac kids, offering a reward to the winnernote which is revealed to be a diploma near the ending of the episode. The kids start wondering as to what the prize could be and start making guesses, with Rolf in particular guessing that it must be a jawbreaker. You'd Expect: The kids would wait for Double D to say what the prize is. Instead: They automatically assume that the prize is a jawbreaker even though Rolf was the one who said it, and run off before Double D has a chance to complete a sentence and tell them otherwise. They then act surprised when Double D reveals that it wasn't the prize, with Rolf and Sarah calling him a "swindler" and a "rip-off artist" respectively for "promising" the jawbreaker. (The latter even still does so immediately after Double D reminds them that he never once used the word "jawbreaker".)
"For Your Eds Only", Edd makes a super-gum formula and Ed manages to easily chew and make a bubble with it, something Eddy couldn't. Ed then crashes into Sarah's room because of Kevin and runs away with her diary. Sarah then corners the Eds and prepares to beat the three of them into a pulp. Eddy then remembers they have the super-gum formula and takes it out of Edd's pocket. You'd Expect: Eddy to give the gum for Ed to chew. Instead: He gives it to Edd, the weakest of the gang. If Eddy himself couldn't chew the gum down, why did he think the weakest member of the gang was going to pull it off? The result was predictable.
In "A Case of Ed", Ed and Eddy trick Edd into thinking he has a fatal disease. The prank involve a diagnosis from "Doctor Ed", who is just Ed, dressed as a doctor, acting like himself and saying random things. You'd Expect: Edd (known for being The Smart Guy) to become at least a bit suspicious, the moment he hears the words "Ed" and "doctor" in the same sentence. Instead: He falls for the trick and actually trusts his idiot friend as a doctor.
In "Brother Can You Spare an Ed?", Sarah gives Ed money to buy her and Jimmy fudge. Eddy notices that this is just enough to buy jawbreakers. You'd Expect: Eddy to realize that doing something that would make Sarah angry would be a phenomenally stupid idea and let Ed buy the fudge. Instead: He convinces Ed to buy jawbreakers instead, against Double D's protests, who is coerced into the scheme as well. Then: After realizing what he did, Ed justifiably freaks out, as does Double D. You'd Expect: Eddy to realize that he just created a huge mess for himself and his friends and panic as well. Instead: He tells Ed not to say anything and Sarah will forget all about it. Does Eddy really expect 'Sarah', with anger issues out the roof, to just forget about this. Even if Ed doesn't tell her, she will persist until she finds out. The Result: Sarah comes asking about the fudge when she can't find it. Ed gives in and admits he spent the money on jawbreakers. In order to spare Ed from Sarah's wrath, Double D asks if there's anything they can do to compensate her. As a result, the Eds are forced to spend the day doing whatever Sarah tells them to do. Where those jawbreakers really worth it, Eddy?