Engine Braking
Engine braking in F1 (talked a lot after introducing comon ECU in Formula One and abolishing "ENGINE BRAKING" during 2008) is really short for a lott of things the active differentials and engine management did under braking. Firstly, hard on the brakes and the differential is locked to stabilize the car in yaw - Honda attempted to do something similar with the front a few years ago, but it was banned.
Secondly, the engine management was thought to allow tuning of the brake balance corner-to-corner, in that the zero-throttle fuelling of the engine too could be altered to provide full engine drag or none to the back wheels only, changing the brake balance considerably. The cars "knew" where they were on track via sophisticated GPS systems.
Finally, the system could detect the onset and offset of rear-wheel lockup under braking and give power to the rear wheels and control a differential slip or input to individual tires, although nobody ever confirmed this. If control system detects any rear wheels blocking during braking, engine management blips throttle to prevent it.
