ITB Split/Multiband Mix Processing

[khameln]

I'm curious, do any of you use warming plugins in multiband when you mix tracks ITB? For example, have you ever split the 2buss and used a warming plugin like Colortone just to smooth out the highs, instead of on the entire mix?

In this case when I say "Multiband" I'm think more along the lines of the Tony Maserati style of actually splitting the mix, instead of with a single processor like C4.

Additionally, for those of you that do this, what filters have you found to be the best for splitting, and more specifically for minimizing phase problems?