Love suspension geometry 101!! There are so many factors involved in tuning the dynamics of a car. Even the wheel design (and tire), which has its own spring rate, can have an effect. On one of my car programs, the wheel design/stiffness needed to be revised to resolve an issue with the suspension tuning. The studio was not happy with us!
The computer has made suspension modeling/analysis so much more precise - I recall we started using it in the mid-Eighties.
Is the bad bump steer common with Panteras or an issue related to Donny's car set-up??