Yes, I was referring to "unzipped," with the conductors very close and held in place by their original insulation.
On 40m, the difference, if you're feeding a resonant loop, between "unzipped" (70 Ohms) vs. "zipped apart" (450-600 Ohms) should be essentially nothing, because the line loss will be extremely low either way. However, if you need to feed the 40m loop on other bands where its impedance might swing wildly, e.g., 20m where its impedance can get very high, the "zipped apart" (open wire type) construction will work better.
73 de Steve WB2WIK/6