Rommel said:
- will the total DC resistance (loop resistance) increase in a spiral braiding?
Yes, it will. But it will be very little increase.
Rommel said:
If it does, will this have an effect on Luma and the color differences - essentially reducing the component signal level - considering no AGC?
-Rommel
No. The drop resulting from the resistance increase will be very, very small.
What the shield resistance increase does to loop intercepted external e/m fields is a different story.
What really scares me with this style of construction is this: by flexing the cable, it is possible to either connect or disconnect neighboring conductors, and that will indeed affect the width of the continuous metal, which will in turn affect the eddy currents within the wires. Enough flexing, and it is possible to change the characteristic impedance locally, and not uniformly around the cable, but on a side... That assymetry in the coax lends itself much more to external influences...
I really love the spiral construction for normal work with audio, as it is so easy to strip and connect the shield..but for apps requiring a good transmission line, I would stay away from it.
I cannot answer how it would affect chroma...I can't speak very intelligently about the color burst/chroma/luma time coherence issues.
Cheers, John