Does Shield Master removing shields' two-weapon fighting penalties mean I don't take any penalties when dual wielding shields, even if I don't have the Two Weapon Fighting feat? I plan on getting Shield Master through the Weapon and Shield ranger combat style (gained as a slayer talent), so I won't have to meet its requirements.
e.g. If I have normally a +10 Attack Bonus, and I wielded a Kukri (primary) and Heavy Shield (secondary):
ShieldMaster(no TWF): +4/+10
So then if I wielded TWO Heavy Shields:
ShieldMaster(no TWF): +10/+10
Is my logic right here (e.g. Shield Master when using Dual-Shields makes Two-Weapon Fighting not needed? Or does Shield Master do less than that)?