i noticed that in Niftski's WR run he Wrong warped in the first room to the end of wall jump. i have tried this myself too however most of the time it dose not work. sometimes though i warp to the final room or turn around room and i would think if done fast this would save several seconds.

you have to get Mario very far to the right of the screen and then enter the pipe without having the screen scroll during the entry otherwise it doesn't work.

Also, it's impossible to warp from the 1st room to the turnaround room or last room with that method, unless you can somehow provide a video proving me wrong

The warp destination depends on the last warp loaded into memory.
In the AISSON run you have the underground warp in 8-2 still (partly) in memory.
If you die and continue, it won't work the same as when you first entered 8-4 coming from 8-2.

i got proof. should i post to youtube?

What? How did you do that?

Did you cheat?

Yeah the whole thing with the last room that was loaded applies here. In this case the last room loaded was the 3rd room (since you were there before dying and restarting the level), and so since you didn't hit the trigger to load the next room, it sent you to the 3rd room.

oh. so its only possible for runs where you die. still helps if you have a really bad time and die.

and i died in 1st room not turnaround.