I don't agree with that at all.
If we can accept that HP damage is a combination of wounds and luck/karma/fate, why can't restoration of HP, through any means physical, magical, whatever, also be a combination of wounds and luck/karma/fate?
You can, but you end with the situation of a character bleeding out on the floor 6 seconds from death being recovered and refreshed by a good talking to from his company sergeant.
This is one of the reasons for split pools originally -- to give a pool that is hard to heal and a pool that refreshes more quickly. At that point, the sergeant can restore confidence, resolve, some karma/luck/divine favour, but only bandage the physical injury gained.