Cool idea I think.
In Texas as a first responder we were never allowed to remove helmets - EVER. As a matter of fact my helmet has two tags on each side informing the paramedic not to remove the helmet until I am at the hospital.
Now I know this is TOTAL FREAK ACCIDENT. But I saw a nasty motorcycle accident back in high school. The guy wiped out bad, with the bike doing helecopters on the ground while skiding and wacking him a few times. His helmet took several serious hits from the nike, stand still debris and just whatever. The details escape me no but the fact that the guy got up, walked around, and was talking to paramedics when he pulled his helmet off. Some how he managed to crack his skull in such a way that the helmet was sort of holding his head together. Soon as the helmet came off he was on the ground with his lovely jellied skull dead as a stone. Of course this was back 1987, helmet technology has greatly improved since. So much, that the economy model helmets of now beat the Top of the line helmets of then.
Anyway I think it is a great idea. Any amount of true help at this point (after a crash) is great.