Scott is using a Dynojet inertia dyno, which isn't programmed for any particular acceleration rate. It just has a big drum of a known mass moment of inertia riding on pillow block bearings, and a simple optical sensor that tells the electronics every time it completes a revolution. The electronics calculates the horsepower from the speed and acceleration rate of the drum, knowing it's mass moment of inertia. Since the circumference of the drum is also known, it can also calculate ground speed. If a tach pickup is used, it can also calculate torque, since it knows horsepower and engine rpm. It's kind of a weird torque number though, it's engine torque, i.e. upstream from the gearing, but including drivetrain losses.
So a first gear dyno pull will happen really quickly. A top gear dyno pull will take several seconds. Results are similar in each case, because even though the acceleration rate varies, so does the speed range. High acceleration at low drum speed (i.e. a first gear pull) indicates the same horsepower as low acceleration at high drum speed (i.e. a top gear pull).
Anyway, Scott, on my Dynojet, the speed is a little off from what I would get turning that exact same rpm in that same gear at the Salt flats, primarily due to wheelspin. Wheelspin is essentially zero on the dyno, it's never zero at the salt flats, at least not at the speeds and power levels of my bikes. Maybe for a sub 150mph bike or something you can ignore wheelspin.
The other thing about wheelspin is that it's different every time I go out there. I use a spreadsheet to calculate gearing and choose sprockets. But until I make the initial pass and get a handle on how much wheelspin I'm getting, I don't really have my arms around it.
I would advise that you gear your bike for the class record, at the power peak rpm, or maybe slightly higher, based on some wheelspin assumption. Start at maybe a 5% wheelspin assumption given the power level and speed capability of your bike. but depending on the weight of the bike, and the salt that particular day, it'll be different.
I can send you a copy of the spreadsheet if you'd like. It's in Excel.
Don't be afraid to gear it slightly short. The physics would indicate that you want to the motor right at it's power peak, but historically, my bikes have always wanted to be geared slightly deeper and taken slightly past the power peak rpm. That's where they seem to get their best speeds. YMMV.
You certainly don't want to be below your power peak rpm when the bike runs out of poop. That really makes for slow speeds, in my experience.