How intelligent do you think Zack really is? I think half of his stupidity comes from the lack of education. He did have some moments of intelligence, like when he was trying to figure out the writing of Ray's name.
Actually I think Zack isn’t that dumb.
You’re right, half of his stupidity probably comes from his lack of education and when he tries, he can do it. He read Ray’s name, but at Eddie’s floor, he also thought of going to the other room with a crack on the wall because he deduced himself that it was connected to the room where Ray currently was. He deduced himself as well that the rock in front of Ray’s tomb was his tomb. He thought of asking Ray to get a lighter weapon for him in Episode 3 after he was hurt. He can wrap and unwrap his bandages himself. Once Ray told him that the cell bars were made of steel and he tested it once, he knew not to hit the bars again. In the game, he himself thinks of the vent as a place where Ray hasn’t searched yet in the poison room. He has survived alone during all this time without ever getting caught by the police.
Also, the syringe’s room: he plans things out, there. If Ray dies, then he’s basically done for. However, if he dies, then Ray will have a problem, and as Cathy said, the syringe’s serum is not deadly. He think about that and that’s why he takes the two syringes. Knowing his vitality and strength, plus maybe the effect of the vitamins, he had good chances of surviving. Zack taking the two syringes was actually the best decision to get out of this dilemma.
So yeah, he’s not an idiot. If he had received a proper education, went to school, etc. he would probably be way smarter.
But as his resumes says, thinking is not his forte and he’s poor at planning. He just doesn’t think things through. That’s not how he works. He’s someone who acts a lot on instinct: act first and think after. He doesn’t take his time to think: when he has an idea, he goes for it.
That can be really stupid (aka breaking the card in the poison room, thinking that Ray could have gone through a locked door at B6) but that can also be really useful (aka throwing Ray into the vent) because he doesn’t ask himself too many questions.
He doesn’t hesitate often. That’s not how he works. He does things and if it doesn’t work, well fuck it. Planning is not his thing.
That could come from his childhood, with survival instinct BUT SURVIVAL INSTINCT SHOULD HAVE PREVENTED YOU FROM SITTING IN A SUSPICIOUS LOOKING CHAIR IN THE MIDDLE OF AN EXECUTION ROOM, ZACK.
So I would say that Zack is naturally not a thinking person like Ray - he wouldn’t be a top grade student for example - and his lack of education doesn’t help. However, he’s far from being a complete moron: he has an instinctive kind of intelligence and can be quite clever.