I have been treatment free for about 15 months now. I mean that in the "truest" sense - no manipulations or additions of any kind for the purpose of combating mites. The bees have struggled, and one could say that the treatment free approach I'm using is "not working" very well. So I have been considering my alternatives. And I find myself wondering if it's really fair to ask treatment free to "work". Isn't it really just choosing a different way to approach beekeeping - one with a certain set of challenges that must be overcome? One could say that it's "living with mites", but then again, that is what everyone does. I feel like it's often just about living with mites, and not fighting them directly.
I quit treating last April, and entered last winter with 11 hives. Came out with 8. Lost two or three through the spring and early summer and have built back up through cut-outs and swarms to 18 at this point. I have just set up nucs for the year. 10 of my number are those nucs.
Over the last few years I have done a lot of study; reading everything I could find on ways of dealing with varroa, working with the bees - and in the end, I feel that for me personally, it just make the most sense not to interfere with the mite.
At the end of the day, I've come to believe that keeping bees without treatments (for the most part) really just amounts to managing bees with mites. Sure, you can graft from your best and work toward a more resistant bee, but with most of us living in areas where there are plenty of other, treated bees around, your progress could be slow.
Many people who are treatment free talk about making increase from "catching swarms" and "feral survivors", but I believe that most of those bees are just swarms from other people's treated bees, so all that collecting just amounts to replacing lost bees with new bees. The only difference really is that you worked for them, rather than paid for them, and in many cases, you can at least count the fact that if they came early enough in the season, the queen probably wintered at least once in your locality.
There are so many challenges that face bees (pesticides, pests, disease, weather) and beekeepers (economics, pests, disease, weather, insanity) that the death or poor performance of a colony could be the result of any combination of things. Mites are one, albeit a major one.
If you look at treatment free in the broadest sense; across all the people who take that approach, it really isn't about some genetic secret. It isn't about small cell. It isn't about not feeding sugar syrup, pollen sub or using three deeps or all mediums. There really isn't "a solution" in terms of some remedy that will rid the bees of mites.
It's about not treating.
So from what I can see, it really boils down to not fighting mites, and then managing day-to-day, month-to-month around the results. It's about deciding that you don't want to artificially combat mites and then replacing the work of doing so with other work.