It's not a matter if they can tank it, it's a matter of if the healer can heal it.
[You must be logged in to view images. Log in or Register.]
In a solid group with good dps and a healer who isn't an idiot you can destroy almost anything that doesn't two-shot a tank. Having the pseudo-tank with decent ac and hps is key too.
As you know healing is a factor of tanking efficiency. CH is a key of the more hps the better. Maintaining efficiency is the important thing once you get past the "can it be done?" question.
At least Ranger's can keep aggro with spells. Often that's where half your healer's mana goes...to the rogue...then the monk...then the wizard. Etc.