I gots the scoop on how this guy did his thing.
He uses the emulator Famtasia. Famtasia allows movie recording, and you can use savestates whilst making a movie. If you mess up, simply load the savestate up and try again, and the movie won’t record you messing up. So, doing this, you can make movies of perfect speed runs and whatnot, and nobody will be aware of the mistakes you’ll invariably make.
…Or so they’d like you to believe. The dude has the .fmv file of his speed run (Famtasia movie file) available for download. .fmv files DO keep track of how many “re-records” are in a movie, that is, how many times savestates were used. Turns out that he used no less than <b>40267</b> savestates to make his perfect run.
Knowing this takes a lot of luster off the speed run, but it’s still hella cool to watch.