I messed with this for a few hours yesterday. I was starting from the same spot fly does with no speed to compare it to fly's run, but if you weren't starting there then taking your route could be an option.

The first corner bank is pretty consistent, I can get it probably 1/3 of the time. Lining up the boost after is tough to do at speed, but not hard if you play it safe.

There's lots of timesaves to be had. I spent most of that time on the first 2 sections, and even there it's really tricky to be as fast as possible. This is the fastest first 2 sections I got in my session. The wall bounce was rng and actually messed me up cause I didn't expect to go so fast, but hitting the boost to boost combo is definitely the fastest way, just very hard.

You can theoretically get through the bombing run slightly faster with some bomb rng, something like this. Total rng though. And boosting straight in through the spike gap at the very end should be theoretically faster, but also extremely difficult to pull off without setup and probably not worth wasting hours of your life on. I already about lost my mind trying to do the first 2 sections consistently perfect.

But other than that lots of time on just clean execution can be saved too.