In the current world record run, there is a part where the runner zips up the cliff, and then uses the jet pack to descend down...

Are there other places you can do this? Can you maybe skip some sections of the train level for example?

no jetpack in the train level, only other levels this can be done are sewers and xizors palace. we do it in the sewers to skip a big chunk of the level to get the gate key and then later to skip the boss, there is one in xizors palace but its tas only for now as no one can work out how to do it. The major jetpack glitch is done in gall spaceport any% to skip from the atst room straight to the boba fett fight and i do it anywhere i can in gall spaceport 100%. this glitch only works well on the n64 version of the game if you are playing on pc there are not many places it can be done.