Best is a weird term.

Im not sure Id call a monobloc best work. The skill to knit two chopperlump barrels together seems more best to me. But, my money would still be on a monoblock gun passing the old French triple proof level of 27,000 psi. Because, it was mostly monobloc guns that did. When Kennett pointed out it was a rare piece of steel that had those 4 crossed sheaths of wheat stamped into it, he wasnt kidding. It is easier to put a monobloc set of barrels right if something bad happens to a tube, but, the world hasnt needed a whole lot of that skill, to date. Nobody specializes in it, that I am aware of. The Bruchets did one, here and there.

Geo, it is both. Ive never seen an invisible sleeve. Ive seen messed up handling, two tone blue, Damascus sleeved to steel, and pictures of all of the above.
To me, finding a better example seems like a much better option. I can hardly believe all the guys piping up about how much cheaper it is to buy a sleever than an example in good condition. Why, finding an example of this with good barrels is almost impossible, and look how economical it was with the sleeved barrels!

Yea, maybe.

Whatever.

Best,
Ted