I have only seen mentions of this on Youtube.
Basically, the Mod Wheel and Aftertouch sliders can be put in between the parameters, and control both at once!
It's a bit fiddly but possible.
Today I found something else: The Arp-time can be 1/32 (or what sounds like it anyway), if you put it in between 1/8 and 1/16
Any one else know about hidden quirks?