Ratnieks may not have been the lead researcher on the project. Hasan Al Toufailia and Luciano Scandian worked on the project as well. It was done largely in January 2013 and the final bit, where they honed in on 2.25g of OA for the best results with vaporising, was done in December 2013, so it was clearly tested as a winter (i.e. broodless) treatment. Maybe the other two did not tell Ratnieks of the reason why they removed the brood - the cock-up theory of academic publishing?
The reason that I thought that "I don't think they really expected beekeepers to open up their hives, lift out frames and remove all brood as a matter of routine" was because towards the end of their paper they said "The third advantage of sublimation is that it is the simplest method, and quick. In particular, because it does not need the beekeeper to open the hive, it is less work and well suited for use in winter (Radeetzki & Barman) when colonies are broodless but not normally opened for inspection." (my emphasis!). Why write that if they expect beekeepers to open the hive remove the frames to remove any brood before sublimating?
As for Ratnieks not wanting to contemplate the 3x5 system, I do not understand why not. In the discussion of the results, they say "The results clearly show that sublimation is the best method in that it gives greater varroa mortality at lower doses, and results in no harm to the colonies". Either sublimation harms them or not - they should not make a statement like that in a published academic paper then get up on their hind legs and say something different with no evidence, at a public meeting.
CVB