The bullocks factor is that Mathis isn't disputing the value of PI=3.1416... for static situations. It changes to PI=4 for a "kinematic" environment.
To show how absolutely ridiculous this idea is, consider a turnatable.
When the turnatable isn't turning pi=3.1416.... When the turntable is rotating PI=4.
So if the turnatable is of a fixed radius, the circumference of the turnatable is larger when it is rotating.
Regards
Steven