pete i have proof..i`ve got a tin of pre-war beans
dont know what they`ll be like..probably crap when fresh back then..especially if everyone raves on about bread n drippin

Johnny, commercial fish feeds are designed with costings in mind, they are OK in terms of nutritional profile and satisfy the commercial fish producers.. However, step across the line and look at bait as an attractor... FLAA etc now start to play a part, carp can detect what they need, they have numerous receptor sites that are quite specific. Ignore the nutritional benefits and look on this in an attractor sense...
Lipids, you are correct that the requirement will vary according to water temperature (and consequent carp activity) but altering the lipid source is the best way forward on this, I have found no maximum lipid level save for the abiity to roll....
Halibuts..... the quantity they are used in....