How to get the perfect starting boost?

when watching replays from top players like Proudster, I see them get a specific starting boost where they get more speed than charging it before 2 goes away like how I do from mkds. does anyone know how to do this?

they are simpaly doing the bowser glitch, it gives the speed at the start (start boost) so its faster but they end up having daisy stats.

this glitch is used for some of the WRs, but not all of them since its hard to do it consistantly. (ex: Mario Circuit 1 uses that strat).

to get a good starting boost, or just the starting boost, start holding accelarate anytime on 2.

I read this topic and I was going to say the same thing as Maximum, but like you said in MKDs, I didn't understand and didn't write anything xd