I want this for a particular reason. The new firmware with 1.7.2 gives the possibility to have two filters running at the same time. I can assign one to the left deck and one to the right deck, but I can't control them at the same time.

The best filters on a mixer are the ones on the A&H mixers. They have a separate frequency knob for each side of the crossfader. That's exactly what I want to do. I want to assign P1 and P2 to control frequency on deck 1 and frequency on deck 2.

Obviously there are many more possibilities for assignable controls in the effects group. Most of them centre around being able to control the effects in both banks without using the deck button.