I recently acquired an EXPUTT and really enjoying it so far.
Have you had any misreads in your testing, as in you take a practice stroke next to the ball, without touching the ball and EXPUTT records it as put?
This happened to me a half dozen times tonight. It doesn't happen every time with a practice stroke but it happens. I assumed EXPUTT recorded head and ball data independently, but it appears the head data has an effect on the ball data? Any thoughts?