I'm sure most of us are familiar with the warmup procedure of the 767b, 787b, RX792p, and really any of the four-rotor road racing cars Mazda built over the years. If you are not, here it is (2:05):
Why do they give it throttle intermittently rather than just just let it idle high or hold the throttle open? What was the engineers' logic behind the warmup procedure? This seems unique to the Mazda cars, most other vintage race cars of the period just seem to fire up and idle in my limited experience.

 

Perhaps to keep the rotor chambers from fouling. I see dragsters do the same thing as well. Revving it to clear it out. If they idle too long, they start to run rich and can bog out.