Why is there a noticeable gap between Casters and Melees?

[Tex_Mex]

We did every turn w/ a 3 melee + 1 BRD config this past week in my main group. It wasn't really any slower from not using a caster, to be honest. Perhaps this would have been less viable when we were working on actual progression the first few weeks of 2.4, but with the gear we have now and knowledge of the fights it's very simple. Could probably do them all w/ 4 melee too.

haha ya, T11 is definitely tough without a caster. And we still use a caster in T10 for 2nd add phase. But it sounds like your progression group is a bit further along than ours so y'all can skip/avoid mechanics on the basis of higher DPS alone.