Moved out of Trivial Issues as this appears to be a bug with how the game works functionally.
It has always been like this my strat as a ninja is to get quited by sprite gods and then zoom across the glands.
You get as many seconds of speedy as you are quieted
You used to - however Deca was supposed to fix it in one of the previous patches and you no longer get infinite speedy. However you do get that ~0.5sec boost, until the game realizes you have no MP to pay to continue the effect