I understand what you're saying but if I see all fingers wrapped around a cue I can tell whether or not that those fingers are death gripping or just firm gripping or lose gripping. Granted sometimes I cannot, it's not 100% of the time but most of the time I can tell if the guy is only lightly holding their cue, or firmly or even very very firmly (death grip).All of their fingers may have been wrapped around the cue -- that would be visible to anyone watching. How do you know how tightly they were gripping? There is a big difference between a light all-fingers-touching-and-no-daylight grip and a squeeze-the-life-out-of-that-damn-piece-of-wood grip.
I know it's difficult to observe this, but to me, I can see it 90% of the time. There are few grips that can fool me. Also, I need to see them play a whole match/set not just one-two shots. If you like do a video of you holding the cue with all your fingers wrapped on the cue, one-time death gripping, one-time loose gripping. but shoot at least 10 shots with each grip continuously. Then ill tell you which is which, just to prove it. Even though I don't feel that I need to prove to anyone but it's just for fun ill do it.