Improved Buckler Defense ?

[drnuncheon]

Not if he is a Dex 12 wearing full plate fighter.

I forgot they added a dex minimum when they folded Ambidexterity in. Ask your DM if you can have the 3.0 version of the feat, or a version limited to shields.

 

[Lonely Tylenol]

Two-weapon defense (and associated feats) are good for fighter/arcane casters who don't want to suffer arcane spell failure by using bucklers, especially if using a buckler would push them over a critical level and screw up their ability to overcome spell failure(e.g. bards, spellswords). As well, the bonus given by TWD improves when fighting defensively, which is also a major benefit for low-armour fighters. Wearing a buckler causes you to suffer a -1 on all your attacks, including the ones made by your primary hand. For a fighter/caster, who already has a lowered BAB, this can be a huge difference, especially since he'll be making multiple attacks each round, and so the -1 (on top of the penalties already incurred by TWF, for a total of at least -3) might make a big difference.

Not to mention that buying a +5 buckler is expensive, and the TWD fighter can invest in other things (like two magic weapons, for example).

 

[The Madhatter]

In view of all this, there is almost no incentive to go shield and sword anymore.

In order to balance things, there should be a feat (or chain of feats) that improves the shield and sword fighting style. I dunno, maybe a feat called "shield specialisation", that doubles the shield's basic armor bonus for one type of shield (a large shield would thus give the dude a +4 to AC, potentially a +9 to AC for a magical shield). Of course, that feat would preclude fighting with an off-hand weapon.

In Races of Stone there are a couple of feats called shielded casting and shielded manifesting which are great for clerics or other armored spellcasters.There is also the feats Heavy Armor Optimization and Gr HAO. They increase your AC bonus from heavy armor and decrease your armor check penalty. Perhaps there will be Shield Optimization in a forthcoming WOTC book or you could houserule it in for small and large shields.