Hotel Target skip [Hotel] Instead of talking to the target on the balcony, open the door and throw something at him to kill him. This skips the long dialogue you have with him if you just run at him.

Replay skip [Mansion] When the replay would start rolling for the last mansion room where the bomb detonates on the door and puts you into interrigation, you have a 1-frame window of skipping the unskippable replay. Currently this is done my mashing the replay skip key(eg. Y for xbox) when entering the door and hoping. Saves around 5s

Copskip [Chinatown] Same as replay skip but much bigger. Skips dialogue, having to get dragon tape from the table and the fight against the 2 cops coming in. This happens when you hit the laserBoss after roulette and exit the room. Mash the replay skip key when exiting and pray. Saves around 16s

Moto transition skips [Mansion] When in the motorcycle level, each time the screen transitions to a new background and the save icon is visible in the bottom right, restarting the level with the R-key or pause->restart saves a few seconds each time. Both conditions must be met! Restarting at a point where the save icon is shown but the background doesn't change, loses time. Can also be done after hitting V off of his bike, to make the fight start immediately.

Slaughterhouse skips [Slaughterhouse] In the 2nd room, cutting the cord of the TV before killing the Terry, disables the sniper and skips the opening "cutscene". After this every other room with a TV can be skipped by rolling past the cameras you can see attached to the roof. Saves a bunch of time and fairly easy to do 1st try in runs with practice.

Bunker elevator door skips [Bunker1] Kind of the same as Moto transition skips. You want to reset when the doors are about to open for a new floor. The first room gets the biggest timesave from this and even that is not necessary. Pause->restart loses time so this has to be done with a keyboard R-key hit to save time. Personally I only do this in the first floor as the timesave is minimal afterwards.