Speculation about interaction of AC and reflex defence

[Reaper Steve]

The problem with Armour as DR, as has been told before by others, is that it's impossible to make an armour DR value that is marginally effective against a Dragon and yet still marginally vulnerable to a longsword.

You know, I can accept that argument... I was just hoping I didn't have to.

From a metagame perspective, maybe this is the way to go.
1) It really can't get much simpler. While I previously posted that having two target numbers (Reflex and AC) could be confusing, I must admit that it's most likely a 'learn it once and never forget' type of distinction.
2) Since hit points actually represent the ability to stay in a fight, they actually provide (and always have) a very elegant mechanic that I haven't seen duplicated in other systems. I don't know of another system that actually measures how long someone can stay in the fight. In other words, if 'AC' was designed to reflect skill in preventing any hit, and 'HPs" tracked actual wounds...then theoretically a guy could fight nonstop until someone seriously wounded him. But since hit points track how much effort you had to use to avoid being hurt, they actually place a restriction on how long a guy can fight, which scales with level. For instance, a guy with 30 HP has enough skill to avoid two 10-HP strikes and the thrid will take him down. A guy with 80 HP can avoid seven.
This interpretation is not possible if AC is replaced by 'Combat Defense' and HPs are replaced by wounds. In this case, a guy could fight non-stop until wounded.

So, HP neatly accounts for skill, fatigue, and damage. But to use it this way, it appears that armor must be used to increase AC instaed of provide DR.

What I would really like to see is a 4E design essay that discusses this in more depth. I'm sure they had some awesome discussions--I'd like to be privy to the rationales.

 

[GreatLemur]

The problem with Armour as DR, as has been told before by others, is that it's impossible to make an armour DR value that is marginally effective against a Dragon and yet still marginally vulnerable to a longsword.

I've got a couple different responses to this.

The first is that I'm not really sure armor ought to be very effective against a dragon. I mean, it's just plain logical that, if you're fighting a giant, steel-chewing monster, you're better off dodging its attacks than trying to block them. It's a damn dragon. Of course it punches through full plate.

The other thing is that I think it's pretty simple to come up with ways for attacks to bypass armor. Simply beating the target's Reflex score by 5 or 10 or 15 (depending on the type of armor) might do the job. Other things like flanking and sneak attacks might factor in, too.