I've solo'd Diablo in hell without moving around much...Yes, as a result, I got picked up twice. So then I started moving to avoid the bone cages. However, I didn't use a single health potion or health shrine.
Things to keep in mind. You need good gear. Good resists. Good dex for dmg and dodge...And above all you need items that give you bonus to discipline. You need at least one bonus of 8-10... I have dual 1H crossbows one with +9 discipline and one with +10. Between this and preparation you can sit there blanketing yourself with shadow power until the boss/mob is dead.
I'm still playing around with switching some things...Also finding some life leech bows (my bows did NOT have life leech on them). And some other things... I'm also thinking about sharpshooter passive skill despite the gear I have giving me 30% crit chance... I was hoping the crits giving chance to restore 1 discipline would help...But so far it seems like that's a REALLY low chance... So I kinda have a passive skill slot up in the air.