Re: squarepeg 2015-2019 treatment free experience
This gets down to needing relative isolation so mating is limited to resistant genetics and starting with queens with some level of resistance. So long as there are survivors, there is something to breed from. Caveat that there has to be enough breeding population to avoid issues with inbreeding. I would not characterize this as "not working", rather "not working as intended".
Having said that, I'll admit hard bond has worked for some. But for others it has not, and is clearly not working in this example.
NW Alabama, 50 years, 20 colonies and growing, sideliner, treatment free since 2005, 14 frame square Dadant broodnest