I think in the absence of BG, the RES would consume many food items that BG normally beat them to. Catch rates for RES in a no-BG pond could be significantly different than in a pond with BG, too.
Since RES are not as prolific as BG, you could think about an alternate predator instead of LMB. Perhaps HSB - you could feed the top predator in lieu of the forage!
In summary, I like this idea! I'm excited about it! It's about time someone tried one of these ideas I've only been able to think about!