While either method turns trains – there are more turnouts in a wye.
Oh
So we are talking about a Y as opposed to a Wye turnout. Bit more annoying for proper DCC operation.
I think this is what it should look like (I planning on moving the gaps away from the turnout to give the rails time to move).
Jack, your wye turnout is wired and joined normally to the oncoming main line that then goes on to form the loop via the turnout. It is at the two split routes of the turnout that you place gaps. Use insulating plastic joiners if you wish. Some guys, like myself, don’t like how they look, so we leave a gap and fill it with some styrene left over from a model kit. Glue it in place and file it to look a lot like it belongs. That means four such gaps.
So, you now have a layout complete, including power feeders up to the two routes on that wye turnout. You have the loop rails in place and gapped right at the place where each end meets the wye turnout.
Now you must wire those dead rails, and you do it the same way as the rest of the layout EXCEPT that there must be a double-pole double-throw (DPDT) toggle switch wired in series somewhere cut into that pair of feeders. There are diagrams on the net showing how to wire a DPDT to reverse polarity. But you must feed that loop. It’s just that you need to be able to flip that toggle once the train enters the loop and the last metal axle clears the gap. From there, you know you can safely cross the gap at the far end.
-Crandell