Looking at Taunts. It's a spell cast of the Physical school. Now altho it is physical, it cannot miss. But it can be resisted. Stacking Hit does not help making Taunts land more successfully. Regarding making Taunts land, the only known item is warriors t3 bonus.
Do items that reduce Spell Target Resistance help with taunts resisting less?
http://db.vanillagaming.org/?spell=25975
If so, how much is 10 Spell Penetration is terms of percentage? 1% for physical?