Michael, I came up with one more obscure reason not to use both sides
of a floppy.. haha.
After wasting a great deal of time not catching what was going on, I
noticed that if I put a DOS3.3 5.25" flippy diskette into my IIgs (with
a DOS3.3 FST present), it would not recognize the disk in GSOS. I
copied and recreated this normal DOS3.3 diskette several times trying
to get it to show up in GSOS. Finally, by accident, I recreated the
disk on a single notch floppy, and it showed up fine.
For whatever reason, there is something in the daisychainable 5.25"
drives that is sensing the presence of that second floppy notch.
Ever noticed this weird effect?