Hi,
sorry, I wasn't able to correctly display the movie, so I understood nothing.
Probably it's some new feature of the latest version of Motion, which I don't know.
I know that two or three years ago, the users' comunity was pushing hard in order to have at least some flex-body instruments to simulate ropes for example. Bending a pipe can be treted same as bending a rope around a pulley, only with a very higher stiffness...
Regards