I don't understand how you are disagreeing with me... If you have to reduce someone to 0 HP before you can hit them, then improving HP improves your ability to avoid damage. Ergo, HP represents your ability to avoid damage.
Look at WotC's implied damage definition again:
Damage is points that reduce hit points.
That's it. HP does nothing to help you avoid damage. HP may help you -measure- damage (if you know what a character's max HP are). HP help you avoid -death-, but even that is in question if you've seen the negative-hit-points-flowchat elsewhere in the forum. If you want to define damage another way, the consequences are on you.
I really don't understand. I didn't say anything about bleeding. Are you saying reducing HP reduces a character's value? No it doesn't. It brings them closer to being incapacitated and dying. Character damage in D&D does not equal what damage is in a dictionary.
I was just illustrating the contrast in definitions.
That is an interesting idea, but it does not address what I outlined as the problem with HP. You'd still end up with either ambiguity between AC and HP or characters with thick hides that can take equal amounts of three types of damage that should, by all rights, kill them.
Example of less ambiguity:
Inigo Montoya's HP by damage type:
Piercing HP 6
Slashing HP 18
Bludgeoning HP 12
Notice how those crossbow bolts took him out fast?
I feel like you may be being facetious here, but if there was a variant that balanced this out I would consider it.
No, I actually like the Death Save the more I think about it. I suppose you could get a +1 bonus per level, and a couple Get out of Death Free cards. Whenever you get hit by something that could cause a normal person to die, you roll d20+character level versus 10. If you win, you live. Hit severity could add or subtract from the 10.
Why does it take more magic to heal Inigo than one of the guards on the floor? (Assuming he isn't ALL dead).
It doesn't. Inigo gets healed to 5 hp just as fast as a guard. Only if you're assuming damage=wounds does Inigo look injured when he has 5 hp, instead of his full 18.