I've seen no evidence that feeding makes my fish less likely to bite. The catfish can't deny that a piece of wiener is far preferable to food. The bluegills (I've caught only two) bit on a little jig and a tiny piece of plastic worm. The LMBs, about half of them feed trained, don't seem to lose their propensity to bite on plastic worm or jig or minnow lure. The feed trained bass are larger (all stocked at the same time and offered 42% fish meal).