There seem to be mixed messages about this in the forum. What exactly does TWF do for Shield Bash? On the wiki it says:
Two Weapon Fighting, whether it has been selected as a feat or from an item, negates the -2 AB penalty when you turn Shield Bash on.
And also:
The Agile Shield Fighter and Two-Weapon Fighting feats can each negate up 2 from the penalty.
So a Shield Basher with a Tower Shield would get -4 AB with Shield Bash on for all attacks, right? With Agile Shield Fighter OR TWF, this would go down to -2 AB for all attacks, right? Now what if one took BOTH Agile Shield Fighter and TWF. From what I understood, this would remove the remaining -2 AB, but only for the Shield Bash attacks. Is this correct?