I think I probably agree with Kevin Perkins. There is much we will never know about fish behaviour, food preferences, and how quickly they forget unpleasant experiences, but I doubt whether a single one would make them averse to a particualar bait. One thought that has been aired many many times is that on reasonably heavily fished waters, where not a great variety of bait is being put in, is that the fish are quite likely to associate a particular set of odours with a good feed, or at least a nutritionally useful item. Just being caught once on such a bait is probably not as much an aversive stimulus as we would like to believe, because we would colour our own experiences on such an event- fish aren't that intelligent. Probably the answer is a little bit more complex. Successful anglers usually think long and hard about presentation, and reading the water- being at the right place at the right time. So, if they all use their particualar favourite, whatever, BFM, or brightly coloured over-flavoured fluoro baits, they will be successful, merely because they have placed baits, with correct presentation, where the fish are, and are feeding!
Several years ago, I tried to answer one question about bait attrractivenes. Using about 40 naive little miror carp (Courtesy of Roger Thompson, Llyn y Gors). The tank (which was a large one- about 2000l, was designed so that shoaling effects could be minimised, by providing some heterogeneity by way of plenty of cover, and artificial weed beds. Really, not much came out of this (an undergraduate student did the work). Basically, the carp learnt to associate the white feeding trays containing the micro boilies with food- we had to get the uneaten food back, via the trays. But the Carp associated these with food within a few days! Perhaps prebaiting is a little ignored here, although using a large visual stimulus, such as a white plastic feeding tray would probably be frowned upon on most waters we fish!!! The only really negative effects were that the fish really didnt like milk protein baits (HiNuVal) flavoured with pineapple, although neutral unflavoured baits were fine. Similarly, Krystons feeding trigger (I've forgotten what it was called) was a distinct turn off, as far as I can remember! Apart from that, all other baits, despite their colour, were taken with gusto, and of course, the fishmeal baits were the best. Oh well, I suppose its just down to using a bait that you are confident with, which an army of field testers, who are much beter anglers that you or I, have proven! Doesn't answer much though.To paraphrase the guy on the "Fast Show" "This year I will be mostly using Nutrabaits Trigga" and a touch of Hi Nu Val , with their Trigga label, and a touch or so of betaine, GLM,and cranberry + peach, dyed brown- a boring bait I know, but its worked just as well as others for me, and is roller friendly! Next, I'll have to find the fish, and not disturb them! Simon.