I am so glad to finally come across a post which has a sense of humor
and at the same time brings forth sound suggestions.
I have searched for a way to establish a method of counting percentages .
not applying the usual methods with hard chemicals .One is the Ether roll,
the other is the sugar roll . Both methods as far as I am concerned are
random and unreliable. The last method which gave a reliable result was the
alcohol/ water method. Of course you kill the specimen bees.
When the powder sugar method was first suggested as a test procedure , I
used it . Results were not in line with the actual varroa drop off with
Fluvalinate as well  as Coumaphose.
Then follows a long story not of interest here.And inconlusive  as of now.

The intereting thing is this: Shortly AFTER this powder sugar test was
published ,I wrote to a contributor of one of the Beejournals of reknown
and ask whether  powdersugar could be applied as your article suggests.
Specifically as it pertains to the possible effect on brood.
The answer was disappointing since the person did not understand the
question I raised.
NOW , the article explains it just right . Thanks !!!!
At this time I have found an insignificant amount of normal "drop off" in
my colonies. I am using  the sreened bottom board which is removable to
clear large debris with a solid board ( 1/4 Ply or 5/16 fiber board )
beneath to serve as a mite count as well as ventilation adjustment feature.
I am at this time use a different method of mite combat but all that is
still inconclusive as I mentioned.
I am looking forward to the day when I can eliminate all foreign substances
from the colony.
Thanks again for your excellent post and get beekeepers on
 the ball to collect data or anecdotal observations. Anything to get rid of
hard chemicals. I heard about sugar without cornstarch but have not found
it either.
Greetings
JDF