now that's naughty; do you know of an instrument that can change tunings as you go? Actually, if memory serves, someone made a revved up piano many years ago with seperate half black keys for differing sharps and flats. Needless to say, it didn't catch on, so references to it now reside in the hallowed portals of Grove's dictionary.
So I'm guessing that if you dial up an alternate tuning on your synth (my Kurzweil modules have a few) you'll only be presented with F#s and not Gbs at the same time.
For the biz on alternate tunings, listen to Wendy Carlos, who's probably taken things as far as possible. Switched on Bach 2000 is the definitive classical version of this, and there's another album who's title currently escapes me where she took things even further.http://www.wendycarlos.com
gives all the info.
Alternate tunings are fab, but for chord notation we're trying here to get a mostly coherent method of labelling for yer everyday muso, rather than your alternate tuning geek.
Dave (pointless pedantic lunatic and proud of it)