There are multiple ocasions were the movement stops for a split second then he gets reseted and does the segment again but this time he is doing it perfect without stuttering and being reset

im guessing that your watching the youtube vid, he just put the demos together in an editing software if you want a live recording

5:31 is a clear put-together of 2 different tries this isnt what a speedrun is supposed to be, he did this with more tries than 1

that's just saving and loading lol

yeah man save loading is allowed in RTA. reason he "he is doing it perfect without stuttering and being reset" is he doesn't load a save/just got the trick that time. if you want to run no save/loading run single segment or SS for short, no save loading/deaths allowed.