Use a pedal to increase/decrease another pedal's level in a pedal-chain while you're playing? That is, can you control effects *levels* with your feet **while keeping your hands on your guitar**? I don't mean clicking effects on/off while playing. I mean increasing/decreasing levels of already clicked-on pedals. For example: Playing through this chain, Guitar-->Hum-Debugger-->Overdrive-->Delay-->Reverb-->Amp could I add a pedal somewhere that would allow me to increase, say, delay on a solo, and then decrease that delay-level when I finish the solo, and then increase reverb for the song's outro? At the very least, if I'm using this simpler chain, Guitar-->Hum-Debugger-->Reverb-->Amp can an expression pedal be reverb-pedal-dedicated so it increases/decreases the reverb's intensity? Throughout this, I want overall volume control to remain at the guitar and the amp. This would not only facilitate gigging, but, for me, recording. I much prefer recording effects & tones from guitars, pedals, and amps than recording clean or straight in and then adding program effects. Excuse my redundancy, and perhaps how stupid these questions are. As you can tell, I'm pretty new to pedal usage, and primitive w/ them. I usually play through one or two pedals and adjust their levels by hand--but want/need to be able to play more fluidly by keeping my hands on the guitar while I adjust effect levels another way. Thanks in advance for any replies/advice.