Instead of cutting the part of the movie showing Your manual operations (turnouts and uncoupling), which is like "Stop motion" (invented by ... George Melies and still in use ! ) in some movies, it would be much better and more "fun" for You to use electric control for the turnouts (Rokuhan ? ), and an uncoupling track if You use Magnematic (permanent magnet by Rokuhan, or switchable DIY solenoid). Unfortunately I cannot write anything about reliability of the remote uncoupling, because I don't use it : my engines (most GP's) stay coupled to the trains when they push back into the dead end tracks, because this procedure is fully automated and it would be difficult to detect the exact position for controlled uncoupling.
Myself I’m using a mix of permanent magnets and electromagnets.
Permanent magnet may be a good solution only for a spur that is due to receive a single car. Maybe two. More than that number, slack action with MTL couplers will mostly lead to parasite uncoupling. Permanent magnets are absolutly to be avoided on sidings or worse on main tracks.
On another hand, I’m totally happy with my #309 Kadee electromagnets, that allow me full hand off switching operations.
But one has to remember : magnet / electromagnet uncoupling only work on STRAIGHT track. To be fully avoided on curves, even the broader ones.