Well, I do appreciate seeing what Cliff has to say in one place. Its very to-the-point. I know this is off topic, but yeks comment above about the WIKI got me reading about Input Trim in Smilefans section.
" * INPUT TRIM: A straight gain control at the Amp block’s input.
....I have used extreme amounts of ‘cut’ on some of my patches when used in tandem with a Synth block to tame the massive, fat signal generated by certain Synth settings."
I always got the impression that the input trim is simply a way to adjust input into the amps power section without affecting tone. So essentially if you want to go in "clean" you can turn down drive and compensate by turning up input trim, or if you want more fatness you do the opposite, at least that's how I've been thinking about it. Does moving the tone stack also help at all in going from dirty to clean or clean to dirty, as opposed to thin or thick I mean.