It's not so bad :-)
I had no problems first time through, using heroes and henchies. I think my usual party makeup does quite well in most situations, just from the large healing base.
Generally in torment areas I party as:
Earth ele (me)
Tahlkora (Prot monk setup)
General Morgahn (Motivation healer)
Koss (Axe)
Mhenlo (monk henchie)
Khim (monk henchie)
Devona (warrior henchie)
wassitname (earth ele henchie)
Like everyone says, when you get to the end just kill the lich and leave Shiro alone completely. Run up to each shrine (Shiro usually lags behind anyway) and take out the margonite groups and cap the shrine. Shiro does next to nothing damage at first. Once you've got all five shrines, run into the middle.
The best advice I can give here is use your hero flag placements! Shiro will own a hero/hench party if you dont control them properly. Make four flag points just under aggro range, and diamond shaped! I.e. in as best text diagram form I can do:
Hero1Hero2 - Shiro - Hero3
HenchiesYou wont have any problems then, as quite simply he can't take out the entire party. So even if one/some of you DO die, they will be resurrected before Shiro can do much more damage. In no time you will wear him down, and out-
him
Good Luck! 