Johnny is totally in the remedial class. I mean, he multiplied his baby and then tried to dye their skin with gravy. He couldn't remember which one was Chris and which was Sam. And he drew constellations all over them. So that's an obvious one. (Though he did at least prevent them from being blown up by his quods.)
Corrie is probably in it too, due to a combination of stressed/bewildered/suddenrageybabythrowing, and then the depression from fighting with Eddie. Even with the extra help she occasionally got and James doing his share... well, she tried after quitting the team, but she didn't have the attention span for the project.