I've been pondering using this rule for awhile now. Kind of makes sense, kind of changes the game a bit.
The only notion that I may be worried about is, eventually as the game progresses to later levels, -every- character can land hits. Could be fun, could be lethal, could be awesome.
Has anyone given this a shot, and if so, how did it go?
Armor as Damage Reduction
Armor in this system keeps all of its normal statistics and qualities, but its armor bonus (including any enhancement bonus added to armor bonus and natural armor bonus) is converted to DR/armor. The DR an armor provides is equal to its total armor bonus with a +1 bonus at 5th level or at 5 Hit Dice, with an increase to that bonus of +1 for every five levels above 5th level, or every 5 Hit Dice over 5 Hit Dice (to a maximum of +4 to DR at 20th level or at 20 or more Hit Dice), provided that the creature wearing the armor is also proficient with the armor.
Using Armor without Proficiency: Creatures using armor they are not proficient with do not gain the bonus per level or Hit Dice to the DR, on top of any of the other normal penalties for using armor without proficiency.
DR/Armor: This type of DR blocks the damage of all attacks that would normally be affected by DR, based on the composition of the armor (see Table 5–1). Unlike most forms of damage reduction, DR/armor stacks with other types of DR. For instances, when fighting a skeleton with DR 5/bludgeoning and DR 4/armor (+2 for armor, +2 for natural armor), the skeleton's DR/armor reduces 9 points of damage from non-bludgeoning attacks, and 4 damage from bludgeoning weapon attacks. Magic weapons and attacks from Large or larger creatures bypass the DR 4/armor, but not the DR 5/bludgeoning.
Natural Armor Bonus and DR: Like a creature's armor bonus, a natural armor bonus is also converted into damage reduction. If a creature is wearing armor and has a natural armor bonus, the creature adds its armor bonus to its natural armor bonus to determine the amount of DR/armor that it has (see Table 5–2).
For instance, if a creature wearing a +2 chain shirt has DR 6/armor is then subject to a barkskin spell cast by a 6th-level druid (gaining a +3 natural armor bonus), its DR becomes DR 9/armor for the duration of the spell. This DR is bypassed by adamantine, or the attacks of Huge or larger creatures.
A creature that has both DR from a source other than armor and a natural armor bonus gains the effects of an enhanced form of DR, similar to how the composition of the armor grants special DR/armor defenses (see Table 5–1). If a creature has magical armor, natural armor, and DR, it takes the best form of the special protection provided by both its armor and its mix of DR and natural armor to its DR/armor.
For instance, if a creature has natural armor and DR/magic and is wearing adamantine armor, that creature's DR/armor functions as DR/—, and can be bypassed by Gargantuan or larger creatures, since the adamantine armor provides the best of the two damage reductions.
I was looking at this part in particular.
Seems like the Damage Reduction wouldn't scale too well, and other AC bonuses become nearly useless as you wouldn't have your Armor bonus fixed in.
It kind of encourages getting ahold of high armor bonuses rather than other things, such as ye good ol Ring of Protection (since at high levels, you'll be struck regardless).
Also, the "Size to bypass DR" sounds a bit strange.
You could do away with BaB... Good BaB =3, med = 2, poor =1. And give iterations as normal. Weapon focus and greater would be worth alot more. High natural armor bonuses on mobs just translates to more DR.
Consensus seems to be too much of an overhaul.
I was going to implement this in our next game but i went over it with my current group, and that was the impression they gave me.
And the table is a democracy. Thanks for the input guys!