Jeff Wilder said:Recovery of healing surges is part of being fully healed. You can be at full HP after five minutes, but probably not fully healed.
One of the better suggestions I've seen for long-term injury, in fact, is the gradual reduction of healing surges. (Something like losing one healing surge per crit, or Bloodying, or both. And it would only return with time or some form of magical healing.)
You could argue that somebody at full hp but down on surges isn't full healed and I could see the healing surge rule, although given that magical healing can be done pretty an unlimited times in a day it might not be worth the trouble of keeping track of.
But either way I'd say 5 minutes vs. 6 hours is more about gameplay then realism. Getting all your surges back in 5 minutes would have a tremendous impact on gameplay.