Peter, I wouldn't dream of contradicting or even questioning your findings, after all that time and investigation on carp baits, I was only saying I don't find the idea of fish "sensing" quality food matching their dietary needs at the time difficult to accept. What an angler can catch on in a particular time and place, given all the variables of food available, baits fish have or haven't met before, or become wary of, levels of competition for any food between fish, the extra "spin" of different flavours, colours etc, though, may not lead to valid generalisations about what works better/best beyond that time on that water, and doesn't necessarily contradict the idea that wild creatures "know" what to feed on to meet their needs at any given time.
As someone who usually goes out with a couple of pints of maggots, casters, pellets or corn or bread or meat and makes limited use of flavours etc, I've no real room to talk, and I appreciate that carp anglers put great thought into bait ingredients etc. I'm inclined to think, and the scientific lit seems to supports this, that fish are more likely to be interested in baits of more rather than less nutritional quality, but the grail of an irresistible or inevitably successful bait strikes me as a chimera because so may other factors mean a bait is not simply a food, and all the factors of angling must shape the fish's reaction to it or readiness to take it. Of course, there are special factors in play when the fish you're after are long-lived, experienced, much fished for and exposed to lots of bait, many of which may be associated with danger. That's very different from how fish in more natural contexts find their food.