Honestly, I can't remember with my 3 big boys, but I know they did lose a lot. 11 lbs is a different category though and I bet you can't use regular standards. Is there such a thing as excess water weight in a newborn?
My biggest was 9lb1oz and we supplemented with formula, but something tells me he lost about 8oz(?) in the first few days and remember he did not have it back by the 2week appt.
I let all of them sleep if they slept more than 4 hours... didn't happen much, but I believe you never touch a sleeping baby. I think a sleeping newborn is healthy... just my opinion not based in ANY medical knowledge or fact.
Do you think maybe it is ok if he loses a little? As long as he is thriving? How are his other development signs such as reflexes, length, eye movement, etc.?