No doubt the solid-solid barrels are strong.
With so much technology floating around I was expecting to see steps towards another direction, that taken by the amateur double rifle builders over at Nitroexpress.com and have barrels that screw into a monobloc. Pieper tried that too if I remember right. Admittedly the Baby Bretton has them, but that is one ugly gun.
Why barrels that screw in? Because then they can be changed individually if and when necessary. Combine those with the replaceable lump shoes of a Parker and a bushing on the cross pin as in the Model 21 and the gun becomes infinitely repairable, a worthwhile consideration for objects that last 100 years or more.
