I generally hate using initials for musicals or movies or whatever. I far prefer using a short form of the title, just as one does in conversation. Merrily, Fiddler, Forum... it's 100% clear what those are, and they respect the actual title, which initials do not. Coming across SITPWG, MWRA, etc., even in context, tends to stop me in my tracks as I have to remind myself what in the HELL they stand for. Even the effort it takes (for me) just to type those is laborious and unintuitive.