Is he solo'ing? OT'ing? I would get rid of Defiance at least. For either option, there's no reason to generate that level of threat, and if he wants to deal maximum damage, he shouldn't be in Def. Stance anyway. Not sure I'd put points into Improved Disciplines either. Imp. Mortal Strike and Endless Rage may also become redundant at that point. I might try to get to Enrage in the fury tree at least. If he's using 2handers, he should probably look into the 2H DPS build in the FAQ thread.
Mortal Strike/Fury:
http://www.wowhead.com/?talent=pVMcbAioM0zZVxzm0go
Arms/Fury:
http://www.wowhead.com/?talent=pVMcbIbZVxzmMgoizio