If it's a true NTSC limit then it should be 60/1.001 = 59.{940059}fps :)
Funnily enough this would also cap b/w TV recordings, which were exactly 60fps.
It's either on the ZSNES board, or an old instance of byuu's forum, or in the old SNES9x forum (unlikely). I'm looking for it but haven't found much yet.
Many games rely on WRAM bytes set to 0x55.
https://wiki.nesdev.com/w/index.php/CPU_ALL#Power_up_state
byuu did read out the SNES WRAM content iirc. There are some patterns that can be observed, but nothing definite. It varies with SNES model, temperature, if the SNES was turned on before (and how long ago) etc.
Air Strike Patrol uses an effect that only affects the graphics output; speedruns created on BizHawk will play back on a real SNES regardless of that. So the only disadvantage that emulator users have is that they can't use the shadow (which doesn't matter much when you have rewind).
You mean slowdowns?
IMO correct CPU emulation is more important than correct video/audio emulation...
If you want to play back TASes on real hardware, you better verify (rather than trusting your eyes) that your emulator is absolutely accurate.
That's already a big hint that it's not accurate.