It sounds as if the rules for healing are a holdover from RQ, where player characters had general hit points as well as locational hit points.
Go for "per location" as a rule. I mean, the character's body might be wounded in a number of locations, but the body's not just going to look at the abdomen and say "Sorry, mate, I can't heal one of your hit points just now; today's hit point recovery's going to your right arm."