Further thoughts on multi-guitar gigs (I could've..and should've put these into one message, but had just got in from a gig and was pretty tired, thus wasn't as organized mentally as I should've been...):

On my "oddly tuned axes", they each have special string sets, i.e. for DADGAD, I use mediums for the low D, high A and high D, lights on the other 3 (56,42,32,24,18,14 - low to high)...on the DADDAD guitar I use a set gauged (this is a 12-string, remember) 24/52,16/40,12/28,12/28,16/16,12/12...this would totally DESTROY a 12-string tuned to "normal" pitches!

I find the guitars work better (stay in tune more dependably, play better) if you don't try to "get by" with the same gauge set-up for all tunings.

And, I'm paid to SING, PICK and be ENTERTAINING...not tune/ retune guitars. And I like my job.