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Hmm; downplayed Power Up Letdown would work here, but I kind of sense a sister trope to that and Do Well, But Not Perfect- the optimal route is to avoid the short-term Min-Maxing option for long-term minmaxing potential.
I'm actually replaying Fallout:New Vegas and a number of perks are like this; delaying things like auto-healing perks, damage-resisting perks, and duration-extending perks till later levels pays off by speeding up progress on various challenges of the sort you're talking about, several of which grant very desirable bonus perks and XP.
Edited by Scorpion451
Something similar to Power-Up Letdown, but not so much a letdown as a temporary inconvenience.
In this case, a game perk that increases the length of time a buff spell stays active. The game also has a perk that's unlocked by casting a certain amount of spells. So while grinding for the second perk, the first perk is inconvenient because it takes longer to reach the number of spells even though spells lasting longer is a positive effect.