I get that this is sarcasm, but one of my idle day dreams is a safe, simple, mostly analog system that does exactly this between a set of moving train cars and the last car on the rear (as a transitional state, the rear car eventually catches up and mechanically couples). I call it the reverse slip carriage. If it can be done, it would keep all the advantages of trains while also totally revolutionising possible service patterns. You could (for example) have a train where every carriage slips-off to make its own subset of limited stops and then slip-joins the next train to pass by. Passengers pick where to wait on the platform based on their destination, and there's always an express carriage to where you want to go. Another neat service trick this system could do is to have an 8 car subway which runs every 5 min that splits itself into 4 different 2-car light rail services every 5 min (rather than 4 subway branches with an 8 car train every 20 min (looking at Rockaway beach A train)). The ability to split and rejoin trains on the fly without stopping or spending time on coupling procedures is simple yet it would be profoundly game changing.
My current vision for the system basically amounts to electrically coupling the motors of the carriages such that any attempt to accelerate / decelerate one carriage transfers energy via induced voltage which accelerates / decelerates the other carriages by exactly the right amount. It's like an electrical version of how all the cable cars are holding on to the same rope. No computer, no glitches, entirely dumb components.
My current vision for the system basically amounts to electrically coupling the motors of the carriages such that any attempt to accelerate / decelerate one carriage transfers energy via induced voltage which accelerates / decelerates the other carriages by exactly the right amount. It's like an electrical version of how all the cable cars are holding on to the same rope. No computer, no glitches, entirely dumb components.