On a DCC layout do you gap both rails or 1 rail & which one if only 1 for signal current detection?
On my test bed using Team Digital inductance block detectors, and a PA, I only needed to gap one rail.
I think as long as you gap the same rail each time, you’ll be OK.
I also think if you have different power districts, that’s where you’d gap both rails.
It mostly depends on what block detection system you are going to use. At any rate, if you are trying to decide what to do about gaps while laying your track, don’t do anything. Wait until you get your detection system. Then you can use a motor tool and a cut-off disk and cut them where you want.
As long as your detectors are DCC capable, gapping a sing rail is just fine. There are limitations:
Do not cross power districts or boosters - you may need optical isolation units to get across them!
Jim