Watching that Fairfield Vintage video, makes me think a lot about how you would gear and set up a vintage bike for a track like that.
You've got the twisties going there but also quite a few long open stretch's to hit them taller gears. Just have to have the horsepower and torque for both ends. One of my shortfalls is not getting enough seat time on my bikes to know 100% which way to go on bike changes. For a long while there I kept believing that I needed a larger rear sprocket because I could never get a good start. But once I got him rolling, he seemed to have good power and speed in 3rd and 4th gear open stretch's. And of course almost never seeing 5th gear.
I later found that, by like my 4th moto gate drop, I was a lot more aggressive on the gas waiting for the gate to fall, and then able to stay up in the pack. So I know that it was me holding back, more than the bike.