esshup the difference you noticed I bet was in large part a result of the protein source difference between catfish food vs. AM (plant protein vs. fish meal/oil).

So far I have not read the study just others' analysis of it. I think that the major point is that energetically the BG don't have to expend energy eating pellets while regular foraging uses significant energy. As a result the net energy gain from eating pellets can be 4 to 5 times higher than normal foraging. This is the first time I have seen the difference quantified. Higher/better sources of protein may also make some incremental difference as well. There are of course possible negative aspects to fish relying to much on just pellets.