Having done 2 weeks of commuting and test riding I have a better feel for how the new aircleaner works.
There has definitely been a modest but noticeable improvement in performance and mileage, but as I suspected, a fair amount of the significant gains I initially observed can be attributed to the the ideal cold, dry conditions of the previous week.
After 2 weeks, and 400+km of both dry and and very wet winter riding conditions, I can say the precleaner is working fantastically, the paper filter element has stayed perfectly clean and dry which anybody familiar with the OE aircleaner will know is a very significant improvement.
I am very pleased with the real world results.
"Take care, sir," cried Sancho. "Those over there are not giants but windmills".