I don't even think it's a cognitive overload thing, it's a "oh shit, you're right, this is hard, skirrrrt" sort of thing. Like telling someone they will do bad

I don't even think it's a cognitive overload thing, it's a "oh shit, you're right, this is hard, skirrrrt" sort of thing. Like telling someone they will do badly on a test and comparing them with a control group that isn't told that. Reverse placebo effect.