The only problem I see is that, if there is a constant stream of electricity through the middle circuit, the PTCT circuit will break. Easily corrected by separating the first pixel of PTCT from the chain.
If you use NSCN to connect to the PTCT it works perfectly.
However if you need to fit the maximum number of separate wires in the smallest space the double wire will do just as well. You can do 2 of these with INSL between for a 5px width and 6 separate wires or 3 2-wire wires with INSL betweek those and you get 5 width and 6 seperate wires.
... I have made a 8bit wire 7px across before, with only 10px wide for the connector, which is much better then the 12px needed before for the connector. Insl actually does micro things down