That explains it quite well. Sacrificing ½cup to save a gallon makes sense.300 or 1/2 cup of bees is whats needed to do a mite test/count. I do 3 to 5 tests per hive per year. OAV treatments do little harm to bees unless a bee gets too close to the vaporizer.
A queen lays 1500 to 2000 eggs a day. During the peak of the season it can get up to 3000 eggs. So a few mite washes a year are insignificant. More are lost each day do to natural causes, mostly foraging.

Wondering if there will be a better way to mite control in the future.

Still another question. Is there a process to protect the queen during the treatment???