The biggest problem to any kind of extensive testing we try to do is that when a fish gets away, we have no idea how big it is. We can't see if there's a correlation between big fish and failed catches. I'm really not sure how to get the right data here to prove or disprove the hypothesis.

If we assume that the chance of hooking a fish is constant with respect to gathering/perception and the only real variable we're looking for here is the chance of catching a hooked fish, we could check how many times fish were caught vs the fish got away with different levels of perception. We'd need about a thousand data points though to minimize the effects of RNG on the data, and that's a lot of data points...