I went to see a revival of GiGi at the Ontario Stratford Festival last year purely to find out what the hell it was doing on a Pink Floyd album. Trust me, it has absolutely nothing to do with Ummagumma or anything else Floydian whatsoever.
It's a ridiculously outdated and sexist musical about old men chasing after little girls. In a bright, cheery, innocent 50's musical kind of way.