Does it actually help with aerodynamics or is it just for bug catching?
It seems that over the top, it would help move the air since there is not as much space between the top edge and the top of your head, but around the sides it seems like it would create more of a problem since there is such a big gap between the back edge and your body.
I keep thinking about them when I pass them, no interest in buying a bent, I just wonder as I'm riding along what purpose it serves. Seems like it is more weight than it would be worth.
If I got a bent, it would end up being a trike, and I'd see about reclining that seat as flat as I can get it while still being fairly comfortable, if I was trying to get some aerodynamics.