[thejeff]

But it still doesn't work.
It's not just the buffs they won't cast.
Only one will cast the Soul Slay or Charm each round. The others will just sit there and take his fatigue.

More effective to use 9 (or 10) shamen. 8 for slaves and 1 or 2 masters. Equip the masters if you want, but they'll get 3 path boosts from the slaves anyway, so with your gear and without buffs they'd be at 5S6N anyway.