>The beekeeper that got me set up lost 457 of his 500 hives 2 winters back so he may be a little paranoid.
And I'll bet he treats for everything and was when he lost them.
Yes, I think the paranoia not only is not productive, I think it's counterproductive. I've been not treating for most of 35 years now and the times I did treat for Varroa I lost them to Varroa anyway.
I used terramycin the first year or two because I was scared they would come burn my hives if I didn't. But it seemed wrong and I quit. That as 1976. I've never used it since. I have seen AFB in other peoples hives. I have never seen any in mine.
I have never used fumagilin or fumidil or whatever they are calling it this year.

Every spring if there was a long confinement there is a little dysentery. I a day or two it's gone.
I've never used apiguard or any other thymol product, nor formic acid nor cumaphos (check mite). I have used fluvalinate (Apistan) and the results were they all died from Varroa anyway. I have used Oxalic acid vapor and it killed a lot of mites. Anymore I don't see any more than a mite or two so I don't do anything.
So now I use not treatments at all. I let them draw their own comb (without foundation), raise their own queens and I just try to be sure they don't starve or go queenless. I lose a lot less hives that way.