Conceptually, this makes sense... Getting there made my head hurt - going back and forth between channels and pixels is going to be incredibly difficult, and maybe not possible in all cases. I tend to start each output on a new universe, so I _think_ it will work. If I had a model that started on channel 1, and another that started on 20, I don't think the math works?
Anyway, I set up a test layout:
P1 - custom, start channel = 511
P2 - custom model, start channel = 1021
PC - custom model, start channel 1
P1 and P2 both look like this:
1 2 3
654
9 8 7
PC looks like this, meant to represent the center row of pixels in P1 and P2
176 175 174 346 345 344