I too shoot the bottom barrel first. It started with the first double I'd ever owned, a double trigger O/U of such dubvious quality that I hesitate to mention its make. The second O/U I owned was a Citori, which is my main go to gun. I didn't want to have to try to remember what happened to which barrels, when I was doing a speed reloading while not looking (diver duck hunting can be like that).
As to recoil recovery, as most of my shooting is heavy loads of 3" non toxic shells, I absolutely believe the lower barrel is quicker to recover from.
Mergus
