Kadee couplers (https://kadee.com) provide a great way to couple and uncouple wagons. They couple effortless when you simply bump into a wagon, even with very low speed / force. Also they are the only couplers of all the different types I have that couple with high probability in a curve!
And then … the uncoupling … simply astonishing! The couplers have this bent iron rod that is attracted by a magnetic field. When pulling a train the claws prevent these metal rods to move sidewards in the magnetic field and noting happens. But once we start pushing a wagon, the claws loosen themselves and they open in the magnatic field, uncoupling the cars, completely effortless! Drive away and you’re loose. (Click images to enlarge.)
Now comes the special trick. When you bump into the train again while the couplers are stil in the magnetic field, they do not hook into each other. The loco can push the cars to any location you like. When you drive away again you’re still uncoupled! Only when you bump into a car without a magnet present you’re coupled again.
It’s great. They are not the cheapest couplers around, but I find them well worth the money.
The movie clip shows the uncoupling, pushing the cars while uncoupled, move away still uncoupled, and finally the effortless coupling again.