> yet simply cutting out whatever drone brood is there 
> on regular inspections appears to help.  I hope to 
> run a controlled trial next season.

When "drone comb" was first made available in "deep 
size" only, I looked at my operation, with nothing
but mediums, and tried taking a knife to my wax combs.

The problem was that cutting out drone cells assured
that the bees would both replace the cut-out comb area 
with drone comb again, and also convert worker cells 
to drone cells as a short-term reaction to the sudden 
lack of drone brood.  

The bees really want that drone brood.  It is part
of their definition of "successful beekeeping", which 
includes swarming, superceeding, and storing only
as much honey as they need to survive winter.

So, the long term impact of cutting out drone brood is
going to be a colony with more and more drone cells,
prompting more cutting, drifting in a slow spiral 
towards having a significant fraction of drone comb.

The "honey supercell" drawn plastic comb denies the
bees the ability to make proper drone cells, so the
bees draw bridge and brace comb to get their drones. 

Worse, having 20% drone comb in a colony (which Tom Seeley 
stated was "normal" in his study) cut honey production in 
half versus colonies where drone comb was kept to 5% or
less.  Seeley did not remove the drone comb when capped, 
so those practicing "drone removal" should see less 
difference, but feeding drone brood through the capping 
stage is "expensive" in both resources and labor.

http://www.apidologie.org/articles/apido/pdf/2002/01/Seeley.pdf

Even when I replaced brood comb with "too many drone cells"
with frames of drawn comb from last year's honey supers, 
the bees still worked some cells into drone cells.  

Another approach to "interrupting the brood cycle" might be
to treat with Oxalic acid in spring/summer, which would kill 
most of the open brood along with the varroa.  
Seems too draconian to me. 

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