Although there aren’t as many levels that this can be useful in, it still can save you from having to do an extra jump or wall climb jump.

The timing of this trick is different to “Double Boosting” in which you have to wait a few tenths of a second after you do you’re “start jump” before doind the second jump. The reason you have to wait is because the “start jump” has a delay after the input you’ve made.

One level it is useful in is 1-10:

It saves you having to slowly slide up the corner of the wall/do an extra jump.