DJ that is a beautiful fish, and might be simply on the decline. If you aren't witnessing a large qty of fish with the concave or pinch belly - you're likely doing just fine! Sounds like you're feeding plenty, at least.
I, conversely, have a much more serious issue I'm contending with where all my BG are exhibiting that characteristic. Talked at length with Condello - he agreed different feeding times would help, as would more aggressive management practices [fyke net]. I'll never have a trophy panfish fishery, and that's not one of my goals, but I'd like to at least relieve the pinch belly syndrome this upcoming season.