People who think the current IB is better than the proposed change haven't stopped to think what main tanking a 24 man will look like in terms of incoming damage.

Sure, Crystal Tower sounds like a lot of it will be three 8 mans that meet up here and there, but I'm sure we'll also have some traditional fights in a 24 man (CT or future content) where one tank is taking the vast majority of the damage in an encounter designed around more than 2 healers being present. Current Inner Beast would be trash in that scenario.