So I decided this morning to remove the top (adjustable) part of the AirFlow to see if I would get increased cooling air flow and also to see how the bike's performance was affected.
Yes, you do get a great deal of cooling air flow without the top part on. The breeze is actually directed to your chest and up your neck into your helmet, at least on me. This would probably be good for awhile, at least until you get tired of getting beat up by the wind, but you might be able to stow the top part under the seat...will have to try that.
Unfortunately for me this morning, we have a southeast storm blowing in with wind to 20 knots or so and it's quite cool today, so it was probably not the best time to experiment in this way. I was getting tossed around a bit (but that would have been the case with or without the top part on) and the breeze flowing up my helmet was nice and icy.
Additional good news is that the bike's performance does not seem to be affected by the absence of the top part, even with the increased "sail effect" my portly self and my helmet provided.
Just thought it was worth a comment. I'll probably be running without the top part as it starts heating up here...in summer, it routinely gets to 95-100F and sometimes holds 105 or more for several days at a time, so the increased air flow will be nice then...