AuraSeer said:It is possible. I think I've seen an official explanation of it, though I can't find the link at the moment. Maybe it was in Dragon?
The way it works is, you use the Regeneration ability as normal, and then apply Fast Healing on top of that.
FH works on nonlethal damage first, effectively just increasing the regen rate. Then once all the nonlethal damage is gone, it starts repairing hit points.