There has to be SOMETHING to note that she's regenerating from obviously fatal injuries.
I'm hardly an expert on all things Touhou, but I thought Mokou didn't have a "healing factor." I thought she simply "revived" from death fully healed. I.E. Cut off her hand it won't grow back. Unless she dies from blood loss, and would then essentially "respawn" fully intact.
Or, to quote Mass Effect 2: "I thought you were dead!" "I got better."
somethingsomething said: I'm very sleep-deprived at the moment, and question my ability to comment coherently, so I'll just do the lazy thing and suggest reading one of the entries on her in the Touhou Wiki: http://touhou.wikia.com/wiki/Perfect_Memento:_Huziwara_no_Mokou