What is short-shifting, brakeboosting and how do you do it? Is short-shifting when you release the throttle just a little over bumps to get some extra speed? I've heard about it but never gotten any real answers to it
Good luck getting answers on this, different people have all sorts of different explanations for it then someone will come and tell you that it is not called 'this' it is called 'that'... I don't know but will have a shot at it for you...
Anyway afaik it is releasing the accelerator (and maybe dabbing the handbrake) then back on the accelerator at the right spot between gear changes. This gives you a speed boost and if a bump is involved then the boost is amplified a la 'curb boosting'.
I do not think using a bump is essential as I have seen people use the technique on flat surface drag races.
Disclaimer: The above is my interpretation of Short Shifting, it is not based on fact just what I have come across and heard whilst playing the game.