Is it viable? Yes, although I wouldn't take it on all party members. The save I play with a friend has cleric/tank, bairdotr w/ glass cannon, witchcraft / wand / summon wielding lady with glass cannon, and Jahan without.
We have to be slightly more mindful of positioning, but we haven't experienced any extreme levels of hardship as of yet (level 15ish on tactical).
Is it optimal? That's another question entirely.
