I'd say it's almost like a walking simulator, I'm just slowing spamming A & D while holding W.

It's not very consistent and will sometimes do the opposite of what you want or just straight up fall so it's not something I can say always works for full-game speedruns. It's almost like a spring I guess.

Walking on boxes also causes you to bend you legs on them, so on level 12 you can spring yourself up to the second platform without having to go to the first one.