This is really the sort of thing I was thinking should be natural among these circles.
Have a bunch of guys play D&D, make a few notes of what happened, who said what, and how -- and then try to make a story out of it. That's essentially how Fate/Stay Night was made.
That being said, it is really weak on side of the author that he literally used D&D rules. Armor class, for an instance, is a bogus stat that hardly makes any sense. So is HP.
P.S: Also, if we think about it as "they played a game and made a story out of it", they are horse-shit level players for saving the PC like that with a deus-ex-machina. A wizard-PC walks off on his own in a forest, ignorant to everything, and gets trampled by goblins. In a normal game, that PC should be dead, or robbed naked. Not be magically saved by a strong NPC.
@boogle
Only current-HP was written, which can be 1/10, 1/5, etc. Go figure.