Zig Zagged: Bob starts out as the smart guy, but then reveals that his intelligence is a result of an Applied Phlebotinum and he is actually an idiot. Then it turns out that Bob lied about the Applied Phlebotinum, and is truly smart.Then it turn out that it was Bob's Evil Twin all along, and the real Bob is smart, just not as smart as he pretended to be in the first place.
Averted: Everyone's smart so there's no definite Smart Guy.
Enforced: The actor playing The Smart Guy has made it clear in his contract that his character must be very wise and all-knowing.
Bob's education was the result of his Education Mama whose regiment excluded anything that wasn't academic, thus explaining his Geek Physique and lack of skills outside academics.
Bob sees his worth as tied up in his intellect.
Bob has a mental condition that compels him to devour any and all information he can come across. He'll do anything to get more data.
The other four realize that Bob doesn't come up with anything much more useful than what any of the others come up with, and because he's The Load, they kick him off The Team.
Bob's mom arranged study sessions and other educational activities in groups of likeminded kids so The Power of Friendship would amplify the experience and prevent anyone of them from becoming over-burdened or overspecialized.
Bob sees his intellect as what he contributes to The Team and feels proud of this but doesn't let it define him.