If you have played Lava Shelter you may have noticed trying to rail switch after the S curve at the beginning is very difficult if at fast speed.

Turns out not only does the game check for you holding a direction, but it also looks for the camera to be in relative alignment. Luckily, we can bypass the camera check by simply putting Shadow in FreeCam. Unlike SA1, it is not in the options menu. Shadow enters FreeCam for a few seconds when you touch the C-Stick.

Here is a video demonstrating the issue on the S curve and with using the FreeCam solution. Note for ILs it is still faster (0.2s per rail switch) to just jump over the egg pawn, but for full game runs this is safer.