Tanking with a rogue (duo w/sham)

[Snaggles]

I would root the mob and balance proximity aggro so you can tank when you want and immediately back up for a backstab forcing it to flip on the closer player (the shaman).

It’s going to be a balancing game. Find the most efficient way to stay mana neutral and high kill speed. Or let the rogue tank the particularly nasty things since they actually have defensive skills.
As for zones, Grobb 45-51/2 and HK in the low 50’s is magic. Nobles with 2k hps drop fast.