By having a lot of little LMB in there, he's reducing the amount of small BCP, and anything that can escape predation has a LOT of food to eat. The suviving BCP will grow to a large size quickly, especially with the minnows in there.
Makes sense...I guess I was thinking that all those hungry smaller LMB would really hammer the FHM-even more than they would the crappie. And LMB are particularly effective shallow water predators, cruising the zone where the FHM are likely to concentrate.