The brakes are independent, so it's not as if one system has to provide both accelerations, one just needs exceptional timing of the feet. A lot of rally car drivers can do similar maneuvers
This is the same reason why the Tesla Roadster has such a killer 0-40mph
He claims in his model, 'his car decelerated at - 10 m/s^2 and, instantaneously, accelerated to + 10 m/s^2 at t = 0'.
No known mechanical system is capable of achieving such an instantaneous jump without a tail-off period. ...."