I did a ride today with a buddy into the Delta ( aerotrunk removed) and topped off after getting back: 113.7 miles/1.549 gal.= 73.4 mpg . There were a lot of hills and the pace was somewhat spirited but it does seem to show a marked difference without the aerotrunk. I may run another short tank to see what it does during more normal conditions. I think my worst tankfill with the aerotrunk on was around 85 mpg so compared with this one ( 73 mpg) it shows a difference of about 16%.
More testing to follow.