When going through the game I was under the impresion you needed three pauses to clip though doors down, left and right, and two for clipping up, but in post-optimization I stumbled uppon a clip to the left that needed only two, on frame 12694, so next step is recreating that on every clip to the down, right and left, if its not something specific to that room, and then check if whatever happened there can be done on clips up to use just one pause.
Edit: So it seems to clip left with just two pauses you just need to jump into the door in a specific way, so it can be done to clip left anywhere.
Haven't found any other magic values for the other directions to reduce the number of pauses needed, so I think I'll do another post-optimization check, just in case and it should be done.