Right now I have three setups hanging in the basement that I'm going to do some rope diameter measurements on (in just a few minutes) both loaded with my weight, and under slight tension. I want to see what all three measure out at with the micrometer.
All three are in DdRT with a V3 ZigZag. The ropes are Drenaline 11.8 kernmantle, Aztec 11.7 doublebraid, and Voyager 11.8 doublebraid.
Tomorrow, I'll repeat with ZZ/Chicane combo, Akimbo, RopeWrench.
SO FAR: Look/feel tell me the Voyager is bigger. Observing the rope where the ZZ flattens it the most, I can tell you that the Yale flattens the most, followed by the Drenaline, and the Voyager flattens the least. Jacket of the Voyager is no looser than the Yale, and in fact the ropes feel almost the same... really good hand, soft, quite firm and close to each other in size. The Drenaline, of course, has a much tighter jacket and firms up harder under tension. You'd expect that from a kernmantle. My prediction is that only the Voyager will be very close to 11.8mm under any tension.
I'll take some pics and post my results. Won't be able to get these in a tree until tomorrow at the earliest. We have an arctic front moving in overnight. Could be pretty horrible by morning.