*Shrug.*  It's good, but not exactly crazy.  Heck, he could get considerably more if he wanted.  Warlocks' blasts scale to 9d6, obtainable through class training, Hellfire Warlock adds up to 6d6 more, and I believe there's an item that adds another 2d6.  Add it all up and it comes out to about 60 damage average.  Stabbing lots of people for as much and more isn't terribly difficult.