They simply didn't pick him up for a gig, and left it at that. He was slowly replaced by Gilmour filling it for him during shows onstage when Syd would just play one note, or simply stand there, and one show they reached a group decision not to pick him up...

I hated to see such a talented mind overcome by a combo of schizo and bipolar, but I suppose it's every geniuses curse.

Makes me scared for my future, hah.