What if you consider the LMB a sacrificial entity, where their only role is as a management tool? I think it can be hard sometimes, to consider a fish in this light, but then again, look at the Grass Carp... their only role in a pond is to help with plant management.
Why then, can we not look at LMB the same way? Where their only purpose in a pond is to control recruitment of the other species present, as well as their own? Certainly, GC will not reproduce whereas LMB will, but maybe preventing reproduction is not the goal here, rather preventing recruitment will serve the same purpose?
I'm certainly not advocating that this plan will work in every pond, but in a pond built with this strategy in mind, no structure or cover, basically a bowl shape, and stocked with the appropriate species, in this case HBG and CC, would the LMB control recruitment of ALL species present? Including their own?
We know that CC and HBG will readily take to feed, so that would seem to leave the LMB few options:
1) Learn to eat artificial feed.
2) Devour every living thing in the pond that will fit in their mouths, including their own offspring.
3) A combination of 1 & 2.
4) Starve to death.
I see #3 occurring in the HBG pond where I'm at. After three years I still have no noticeable recruitment of either species. Maybe that means it's working, or maybe it's getting ready to blow up in my face, I don't know. So far I'm satisfied.
I have nothing against HSB, I have some in one pond and I'm looking forward to growing them out, It promises to be a lot of fun. I just don't want to limit myself to looking at a fish in the same way, or utilizing it in the same manner time after time. Once you remove the notion of having a typical, balanced pond, it may open up other avenues and other means of accomplishing one's goals, however untraditional those may be.
