The question is, what kind of "summer" tires was the British 4wd using? Were they true summer tires, or the M+S rated all weather tires commonly standard on American 4wd and awd vehicles--makes a big difference. My kid's A5 Quattro came with M+S tires. Even with 4WD you're required to have M+S rated tires when chain controls are in effect in CA (not that anyone checks). M+S rated all weather tires are not true snow tires, for those who don't know the difference. Also judging by the way the tires were spinning on the 4WD vehicle that doesn't look like an AWD system.
Here are the tires they used. Their winter tire, on the right, is a Goodyear Performance 8, as they state in the video. They don't name their "summer tire," which is the one one on the left, but it looks similar (but not identical) to the Goodyear Eagle F1 Asymmetric 2, which is a true summer tire, not an M+S all-season:
So my best guess is that the tire they used, based on the tread pattern, is a true summer tire. But I'm not an tire expert.
Edited by chemist - 11/8/14 at 5:54pm