Why are you giving him crappy advice?
I have tried a lot of single target builds and this is the way to go:
Demon Hunter - Game Guide - Diablo III
4 pieces marauders with RRORG + 2 Nats
Stack fire, elite, CD CC, IAS and Dex
Use your templar for the slow.
You don't need the amulet shit with the range position profile. No sentries since in the amount of time it takes to get the sentries up (and do some proper dmg), you would have already killed him with my build.
Kills him in 6 - 8 seconds in T6 depending on how many cluster bombs that hit him.
Rain of vengeance does not suck since thanks to your templar and companions tanking, Ghom will not move around.
I do not know what other shit advice you've given him but this is basically the end game build. The other builds might be some what useful during your time searching for the gear to see the potential in this build.
My bad if this came out cocky, but you really did give him some bad advice guys.
And btw, there are over 430 pages of comments around the profile. Check the main thread out. I am almost certain that you will find better advice there where people actually post good results, rather than creating your own thread.
Edit #1: Oh, come on! Fucking smoke screen?! Was that the best effort you could do in giving him shitty advice or trolling? Either way, just get the hell out of here.. There is no reason to stack toughness on this profile... You won't take damage.