I think there are definitely some terminology differences. To me CIO is leaving your baby to cry till they fall asleep and eventually give up calling for you. I thought controlled comforting was when you went in and out of the room e.g letting them cry for 10 minutes then going in resettling and then letting them cry again etc until they self settled. I don't pick DS up in the night if he is only doing his grizzly cry as I know he just needs a bit of help transitioning to the next sleep cycle so I pop his dummy back in and rock him back to sleep in his hammock. Sometimes he also doesn't need me and likes to grizzle himself to sleep. I stay in the room with him but he doesn't need me to do anything I just see it as his way of getting comfy as he will grizzle and squirm until he finds the position he wants to be in and he is out like a light. If however he does his proper I am not happy and I need you Mum cry I am straight there and do pick him up. It's leaving them to cry like that, that I won't do as I know my son and if he is crying like that something is wrong (usually wind pain) and he needs me to help him through it.