3 very simple and straightforward methods of moving the source-monitor track-selector to the desired track.
But even such simple things can be overlooked in the rush to get to the difficult stuff.

Regards
Douglas

Great tutorial (as always), I actually was unaware of the 3rd method. 

Another thing that you can do is set "Auto-Patching" in your Settings (I believe it's under Timeline) and then whenever you activate tracks (say V3 and disable V1, the V1 on the Source side will jump to V3)

Hi,

Kenton.VanNatten:

Another thing that you can do is set "Auto-Patching" in your Settings

I second this.  It seems like a little thing, but it's a huge timesaver.

good luck,
Carl