This is a Speed Run 2 technique called Wall Tap. This technique originally uses when you want to save your time from falling in a tall height. Normally when you fall from a high areas, you will freeze for a few seconds before you are able to move. With using Wall Tap, you are able to ignore that freezing state and you are able to move freely. However, this technique is mostly used when you wanted to change opposite directions.
Oh is it the one where you jump mid-air just before landing? It helps with making it onto platforms too (like in this week's online race)
@Gave2haze yes and there is several individual levels that can be use for Walltap, however, I forgot which ones.
@Gave2haze to be honest, I think Walltap does not affect time in Speed Run 1, it actually more beneficial in SR2 because if you jump from a high area, it will freezes you unlike in SR1.