I think I know more about my Sciences than any other subject, although I'm not going to remember every little detail. Linear Geography is a complete blur, I guess I only revised it a little (because I could get away with it) and as a result I know very little about it
. I believe modular exams are a better alternative, people just get bitter about it because they had nasty linear exams in their days (the rest of my GCSEs were linear).