So i found a new consistent way to skip the first 2 parts of the game saving around 1:30 minute.
Note: It is required to have the game on 30fps in order the glitch to work.
The buttons are RB = Sneak, RT = Intuition, you do the ledge slide glitch with the joystick on down.
Avoid touching any walls before going out of bounds.
It is important to shimmy to left as early as possible after getting out of bounds in order to maximise your chances of reaching to the final room. This has to do with the range which Trane can shimmy on the X axis is absolute, meaning that the more Trane slides forward-left the less X distance you can shimmy back manually.
Also for the intro, the second train spawns the moment the intro cutscene ends, so it's faster to wait on the cutscene until the 1st train spawns and and then skip the cutscene. The timing is very lenient.
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