When I did have a solid bottom board on a hive, even tilted forward, I saw . Of course, that was in summer, and we did have a humid summer.
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There is no problem with moisure building up. It means nothing.
Now we are mixing very different issues
1) Concensation of water when warm air meets cold bottom-> droplets
2) Too hot inside --> need of bigger opening
3) Too moist on winter inside hive and nosema will turn on
4) Calculating some dead mites
As you see, these things have nothing to do with each other. Only important thing is nosema. Keep upper enrance open on winter.
I treat my mites without calculating them all the time. I put oxalic acid. I save nothing i I not treat them. I can give up to give apistan, it gives me money if I calculate and I notice that there is not need for medicine.
Too hot inside: give more space, take capped honey away, open the entrance wide, take upper openings open.
Do what you do, but don't cheat your self!