I noticed that too, I don't think he's cheating though :/

You can just hold the jump button to do that.

Speedy you can go into the download file and change numbers around, also most emulators come with cheats installed. Like whenever I press spacebar on accident it randomely goes into 1000% speed

If you jump and keep holding down A (Or what ever your jump button is) and you hit a robot, it will give you a higher jump.