I'm planning on making a S&B build, if i take ISB it says it grants a passive 20% shield bash chance which sort of turns it into a standard weapon, like basic fighting with two weapons has base 20% chance of offhand proc.
If i was then to take feat(s) of TWF would they increase the offhand proc chance of the shield bashing to 40/60/80% as it does for *normal weapons?
If TWF feats do affect shield bashing, with the new shields that are around now with much more offensive and powerful abilties randomly generated i think it would be well worth it, but i don't want to waste 1-3 feats taking TWF if it will not augment the S&B style.
Thanks in advance for any answers!