One-way and two way signals: There are one-way signals further down to the right, making these tracks one-line as well. I usually don’t bother changing all signals on a track to one-way, when there’s one set of them already in place.
Yes, the signals just behind the switches are inefficient. But they should in no way affect how the line is drawn over the tracks. Especially, they should not cause the line switching tracks (and they don’t). So they’re not relevant for this issue.
My point, however, is:
As I said in my post, placing the one-way signals within the switch area should not be necessary. The lines should not change tracks, regardless of whether I place those signals, or don’t. There is no reason to change from the lower to the upper tracks here, and the lines should run on separate tracks even without those signals. If I need to place those signals, TF’s pathfinding is odd.
And the issue in douglas’ setting was not about signals. TF changes the tracks on which a line runs when you place switches. That’s the problem. In my example: TF for some reason chooses to run the line on the upper track. I have to force it to use both. And not just once, but every time there is a possibility of changing tracks, TF tries to do that.
In this case, that can be solved by placing signals (even though it shouldn’t be necessary). TF should create the line just like in your image, even without the inner signals.
But there are settings like the one douglas posted, where signals don’t suffice, and TF has to be told by waypoints where a line is supposed to go.