I've done a lot of research and my only guess is fast disc speed only works with the Dual Shock version, if that's the case then there needs to be separate categories or just scrap the PS1/PS2 section because no one has any answers for massive differences between end game times. Hopefully someone can shed some light on this topic.

I'll investigate it later. I don't think Trevor played on a PSP or in any way cheated that run. He played on an SCPH-90001 with Breaker Pro afaik.

"Used a PS2 (SCPH-77001) with fast disc loading enabled."

This is taken from his own video. It is extremely unlikely that he would lie. Trevor is one of the best runners to ever touch this series. He is one of my inspirations. So maybe that version of a PS2 is faster. Maybe we need to carefully compare the runs side-by-side.

7k vs 9k PS2s debate regarding loading times using FDS happens a lot in some other communites where running the disc PS1 version is the only way to go or really popular. I won't be surprised if this has something to do with an specific PS2 model.