>>94714369Watch any episode of Ed, Edd 'n Eddy, and pay attention to Ed's dialogue. Almost everything he says is relevant to the situation at hand, even if the way he got there is only comprehensible to Ed. Even the stuff that wasn't relevant had an internal logic to it (Ed removing Johnny's water heater was done because he wanted it and thought he could "build a birdhouse" with it).
Idiot characters need to be consistent in intelligence and consistent in their own trains of thought, which is where many idiot characters fail: they either only act stupid when it's "funny" and are intelligent all other times, or they are "lolranrumb" train wrecks that take all of Eds non-sequitur moments and crank them up to eleven.