I’m not sure if this is well known or not, but I never see people do it in runs and I just discovered it.
I’m assuming it works because every time you saveload, the train doesn’t move, but think that time is still going. After about 50-60 saveloads, the train speeds up to compensate for not moving. It clips into the other train, which we can use to clip into the metal pole (or the guy with the suitcase). If we saveload down too much, we are just stuck under the train. If we saveload into the train tracks/ground it sometimes works but we have to saveload to stand back up again.