Block: evaluate a homebrew mechanic (3.5) (WiP)

[tiltedwindmill]

Greetings. Despite the shield bonus, I have always felt that a good mechanic for blocking things was lacking in 3.5. But, simply adding 'block' as I envision it would probably have all sorts of balance related consequences that I probably didn't think of... which is where you come in!

Please tell me what you think with regards to any of...
1) the quality of the rule itself (simplicity, playability, reasonable?, etc)
2) balance (makes barbarians stronger, makes feat X broken, etc)
3) other sources/ideas i may have missed (actually, everything you ever wanted to know about blocking by paizo is much better, etc)
4) solutions to problems that you or other forumers have proposed

Block~
When a melee attack is made against a player (but before it is rolled), that player may make an attack roll to oppose that of the attacker. If the defender is successful, the damage is dealt to the weapon or shield held rather than the defender.
-damage in excess of the weapon's hitpoints carries through to the defender
-a player may block once per round
-the block roll is made at the highest appropriate BaB of the defender, with all modifiers that would apply to his attack
-a player may not block while flat footed or otherwise denied dex to AC
-a player using a shield uses full (not two-weapon fighting penalties) attack bonus, and may use the shield to block RANGED attacks.
-the block roll is reduced by 4 for every size category by which the blocking weapon is smaller than the attacking weapon. so blocking with a dagger would take -4 vs a one-handed weapon, or a large light weapon, and -8 vs a two-handed weapon or a large one-handed weapon, etc (a shield counts as a two-handed weapon for this purpose)

i plan to base several feats around this... such as parrying (where your weapon takes half or no damage on success), combat reflexes(block) you can block an additional # of times per round = dex bonus, combat-maneuver+block (when you block, you may make a free [combat maneuver], etc... so i would also appreciate ideas here, but ill flesh that out more later

thanks

[TuggyNE]

A very similar idea was analyzed previously. The basic problem with this is that you tend to burn through shields rather rapidly, which isn't sustainable for adventurers, because nearly all hits produce lasting damage to the shield/weapon. Improved Parry, or whatever you call it, might help with that, but running the numbers is fairly important.

[tiltedwindmill]

That would certainly be true if you were to block all the time, but the mechanic isn't meant to replace AC in every situation (using something this way does not detract from your shield bonus).

When fighting a big ugly monster (who is likely to go through your shield/weapon) blocking should really be a last resort sort of thing. Right? First instinct would be to get out of the way.

It seems much more useful against spells with range of touch, poisoned attacks, stunning fists, and attackers who tend to do damage lower than the hardness of your gear.

thx for the link by the way