Actually I like the way the factory smarts handle this in they automatically flash the brake lights if you break hard from a high speed, I've seen these flashing lights on other vehicles and the default ones get really annoying being behind someone with them as they keep flashing in stop/go traffic. Even with these options you only get a 15 second moment of silence.
It would be nice to have these items not come on if you break from anything less then say 10 or so, anyone know of something like the smart system that is tied also into the vehicles speed?