Ok here are the readings for the 2 tests that I promised to get. Now we have 3 tests done by me and one test by Venture - above - for VD in Loop Runs. Please note that my last fixture on Circuit 3 is a medium base 50W in a light post...so I had to take the bulb out to take the readings....so the loads shown under circuit 3 already excluded this 50 W load ONLY when taking the 2 voltage readings at that fixture. I put that light bulb back to take all other readings shown in this table. (i.e. Circuit 3 bak-up to 275W for Test 1 and 235W for Test 2) For circuit 2 the last fixture has 20W MR16....so I was able to get the readings at the pins without taking the light bulb out. In summary; as I said earlier it seems the explanation of the resulting low VD Looping 12/2, which seems to equate single 8/2 wires, is that 12/2 cable has 65 strands of cooper and 8/2 cable has 133 strands of cooper...so looping 12/2 is actually using 2x65 = 130 strand of cooper which is almost the same - if not exactly the same - as using single 8/2 wires with 133 strand of cooper to that same load.