Having never seen a really low ventilated rib, I suspect that its addition is an attempt to wed the single sighting plane with the double barrel profile. To me, it doesn't make sense to try to achieve the sight picture of a single barrel gun with a side by side. The real advantage of a side by side is in estimation of elevation, as well of course as keeping ones' focus when swinging against a background of heavy brush. The advantage of the over under or single barrel is precision in the horizontal plane of the 90 degree crossing shot. Therefore the side by side really shines on live pigeon shoots or driven, incoming scottish grouse, or departing trap style angles, or rabbits against a brushy background, and other HUNTING presentations. The single barrel profile is winning the clay games, we might as well admit--even if it is a matter of contestant preference. Will an elevated vent rib change that and give the best of both worlds? Debatable, especially since it is hard to shoot and throw up at the same time...Steve
