This tip came about in the User Help Exchange forum, but it really belongs here. It is about the power of using the expression pedal and multiple modlines to get really multidimensional, multithreaded control.
Without further ado, here's Vance:
"I echo Tom's comment that it's VERY powerful to use Pedal as the source on multiple Modlines: I have one Scene in which a pedal turns on a delay when I move the pedal from the "heel" postion, then as I move more toward the "toe" position, it turns the mix of the delay up as it turns the mix of a reverb down. When I get to about halfway through the pedal's travel between heel and toe, a filter is turned on and starts filtering the high end from the delay, at the same point the delay feedback is also being controlled by the pedal movement. RIght at the very end of the pedal travel (near the toe position) a distortion is turned on very quietly but turns up very quickly as I move the pedal just a little bit to the very end of it's travel.
Modlines are amazingly powerful that way!
Thanks Vance, great application of this theory!