Maybe . . except if you have to dump the open barrel in order to get to the tight one, then the bird is further away by the time you fire the second shot. The ability to make an instant selection, as well as greater reliability, are selling points for the traditional double triggers.

On the other hand (to be fair and balanced): If you shoot the tight barrel first and hit the bird but don't bring it down, you're now left with the open barrel for an even longer shot to try and finish it off.