I think this is the best possible dervish build for hero-henching, so I thought I'd share it with y'all:
D/W, 12+2+1 mysticism, 12+1 scythe mastery
Avatar of Grenth
Heart of fury
Eternal aura
"For great justice!"
Distracting blow
Victorious sweep
"Save yourselves!"
Pain inverter
The idea is that avatar of grenth has the potential to be by far the deadliest of the elite forms, and you want to maximize your hits with it in order to take advantage of the 20 life-stealing per hit. That happens to be exactly what you want to do with a "Save yourselves!" warrior too, so why not marry the two and make a versatile hero-hench dervish? With this build, I've been able to hero-hench everything I've tried in HM. That's more than I can say for 99% of the PvE builds out there. My regular sequence is 1-4-5-2-3, then 5 and 6 as necessary, and you can usually squeeze in another heart of fury before having to recycle. That means you're under IAS most of the time. You definitely need a zealous scythe because skills 1-3 use a fair bit of energy.
Distracting blow is a key skill on this bar because you get credit for hitting each affected foe--and that adds up to a lot of life-stealing and adrenaline. Don't be ashamed to use it and don't worry about the minimal damage. This is a life-stealing build, not a damage-dealing build. The interrupts that you get with distracting blow are an added bonus.
I think you want 15 mysticism because it's a handy break point, and it's worth the hp loss caused by the major rune.
If you feel you don't need SY (but then good luck hero-henching without it), obviously you can take off FGJ too, and throw on two of your favorite scythe attacks instead. If you're a PI-hater (but good luck hero-henching without it), throw on your favorite PvE-only skill instead.
In any case, don't bother with earth skills like conviction; you're getting so much hp influx with life-stealing that it's just a waste of attribute points and bar space.
Ordinary Sabway heroes work fine with this build, but make sure that you have splinter weapon in there somewhere. Nightmare weapon is deadly too. You need condition-removal, since long-term blind will debilitate this build.
P

If you really feel you need AoHM, you can pack it instead of pain inverter. I personally think it's unnecessary.
So the extra damage from AoHM doesn't fit you? K..