I"m liking your train on thought FD.
I to have never seen a big cat even though I'm an old f****r now done years of shooting foxes, rabbits and few other thing before the law changed. As said before was doing it for pelts frowned on now with the fur trade gone. Lamping at least 3 nights a week skinning the other days only once did I see some eyes that I knew were different. Can't say it was a Big cat but it was animal quite large and covered some ground very bright eyes, who knows.
But mates I shot, dug and ferreted with have seen them as I have said before. Their accounts are very c