My pond was originally an LMB pond when we bought it.
Over the years, we introduced SMB. Then, we got lucky, and got some brood stock SMB over 15".
For a few years after that, you would catch more smallies than LMB.
Now things have turned back to more LMB than SMB.
I am restocking SMB hopefully in the next week, and will also start a more rigid culling program for LMB.
I've always had SMB reproduction, but probably much less now.
If fact, I once saw a nest that had two SMB and one large LMB in it.
But as the studies show, and the experts say, the LMB will take over. So you just have to restock SMB from time to time if you want that kind of mix.