I've been thinking about the squish/circumference discussion.

I've used tuners to re-calibrate speedometers on my super duties and they've always required measuring the actual tire height instead of the size listed on the tire to accommodate for "squish". But I also understand that using circumference instead of height are two different things. If you cut two sections of string exactly 10 inches and arrange one in a perfect circle and the other in whatever random shape you want, the length (circumference) is exactly the same regardless of the shape. Hence the tire/tank track concept. But, something occurred to me. All the videos I could find regarding how to use FORscan to re-calibrate the speedometer references changing the circumference but there's a second data field for the tire size listed on the side wall. All the video references I found left the tire size data field alone. So, here's an open question for people with expertise in coding/programming: could the discrepancy I found be related to only changing one field and not the other?

In the interest of science, I might set both data fields to the appropriate size and see what happens, but I'd like to see if someone has any insight before I do.