Hey, so I'm not a regular speedrunner of this game, but this is one of, if not my favorite flash game and wanted to share this. This is actually a clip from a while ago, march of 2019, and I was just streaming some sm63 for fun. I was on the final hit of the boo fight, went too fast with the turbo nozzle and crashed into boo at the same time as the spinning wood platform thing. I die and respawn right next to the shine. Idk if this is a known strat, as I said, I'm not a regular on here. Anyways here's the link: https://www.twitch.tv/ampersand_s/clip/PerfectModernJaguarBrokeBack

Hi, Ampersand! That glitch is already Known by the Speedrunning Community. If you bonk into anything on the exact same frame you start the cutscene after knocking King Boo the 3rd time, the shine cutscene and the bonk cutscene overlap enough to cause a death. And as of why you spawn where you do, that's just because the spawn location is set to there.

(but good job finding it by yourself)

I'm surprised you found it by yourself but good job! Sadly it was already known about and was done in runs by AprilSR and even TheGaming100. If you look at the BM IL and you go to shine 3 you can see that I actually got a 58.562 with this trick but the timing to do that is really difficult (you have 2 frames to bonk and hit the Big Boo at the same time)

The timing is actually really easy it's just that if you do it perfectly you can get a faster variant of it