"What I say, in America unefficient methods are widely used among hobby beekeepers. In their hives dead rate in winter is huge compared to professionals. Look the last Maarec report.
The worst is an advice: do nothing, let evolution work!"
I agree with you, many here ignore sound science, and instead want to wave a magic wand of powder sugar, screened bottom boards, etc., and ignore all the sound studies and trials that prove them to have almost no real impact on the pests. Laziness is also a problem, if you dont look for a problems, you wont find them.
That said, when you find yourself in front of a PC, I would appreciate links to sound studies or trials that you say makes the method of O.A. trickling and its route of efficacy to varroa obvious and so ends the senseless debate! I really dont have time to waste searching for a needle in a hay stack just because someone says is there.