Answering the OP's question directly, to avoid being chided by the self-appointed thread police:
I was always still in control at the fastest speed my track bike was capable of on steep descents. Riding with a 51/19 setup (42-inch gear, approximately), I hit around 225 rpm on descents many times over the decades. Scary but tolerable. The limiter with that gear ratio seemed to be wind resistance and not cadence. (Past tense because, at 68, I'm unwilling to test the limits the way I used to.)
The trick seems to be to flick your feet forward with each pedal stroke and to let the pedals drag them around the rest of the way. Trying to pedal in circles at high cadences is a mug's game.