Im not doubting the findings, However I think samples should be taken before a feature in the lineup shoot. Say someone dumps oil or anti freeze or brake fluid on the track and cars run thru it. IMHO that can change the compound. Wouldn't be so sure some armor all wouldn't either.

Guess they know what their doing but in the world of racing I was around, You mounted it up, grooved it and raced. if you did it at the shop sometimes you put it out in the sun to try to stretch it a bit so you could get a better more acurate stagger reading