The result will raise some eyebrows -- it was the manual transmission ZL1 that logged the fastest lap by just over 3/10th's of a second. (#savethemanuals)
And on the track's longest "straight" between turns 6 and 8 (requiring multiple upshifts) it was the 10 speed automatic that pulled slightly ahead, as would be expected.
But considered from strictly a lap time standpoint, that's about the extent of the automatic/dual-clutch transmission advantage. Downshifts are also much faster, but if the braking points are equal (no reason they wouldn't be), and the required downshifts are completed within the braking zones in both cases, then the ease and quickness of the automatic/dual-clutch downshifts doesn't produce a time advantage.
With regard to Pobst's hot laps, our analysis is that he came through Big Willow's turns 8 and 9 more cleanly in the manual transmission ZL1. (The automatic ZL1 was in the lead on entry into turn 8.)
The result emphasizes an old HPDE cliché: It comes down to the driver. A clean lap beats modern automatic gearbox technology every time.
Our own track experiences with manual and dual-clutch versions of the same car parallel Pobst's findings. That is, it's neck and neck and the cleaner lap wins out. But all lap variables being identical, our best estimate is that a dual-clutch transmission counts for just a couple of tenths over a manual transmission around a typical road course.
The 2017 ZL1 stays planted courtesy of new OE Goodyear Eagle F1 Supercar tires.