You may be correct in your analysis...
But I've always been led to believe that what made the original Swiss and later German P-210s better than most other guns was that they were basically hand-fit by master craftsmen at the factory, and NOT because they used Browning's barrel/slide lockup system. The older P-210s were
semi-custom guns built in a factory, and that made them more costly than the average gun.
As it turned out, that eventually made them too costly for the military and police units that gave them their start. As time passed pretty-good alternative service pistols became available for maybe 1/3 the P-210's cost, and demand for SIG P210-level performance diminished.
The SIG P-226 (and P-220) X-5s X-6s are well-fit guns, and a number of the 9mm P-226 X5 models I've seen and watched others shoot, seemed to offer very similar accuracy --
even though these guns also use the "SIG" locking block desin rather than the Browning barrel/slide design. I've had several p226s, and a P226 X-5 (.in .40), and I'd argue those two P226s were similar --but just like VW Beetle-based Porsche 914 was similar to a Porsche 911. (I couldn't shoot my SA X-5 in .40 well at all, but others could, so I eventually sold it. It was a beautiful gun, but it became a safe queen of my inability to shoot it well. I bought it used -- It was an early model unchanged from its factory condition -- and very heavily oversprung. The guy I sold it to was a good home gunsmith, but he eventually sold it too. Some of the springs are different than the P226 springs, and we were kind of stuck.)
A lot of modern guns use the Browning barrel/slide lockup, but they aren't given the same attention to fit and lockup when made as the older Sigs were. Several of my CZs and my Sphinx SDP use that same lockup method - in fact are very similar to the P-210 in that respect --, and the Sphinx is a nicely fit gun. (Maybe not P-210-6-nice, but nothing to be ashamed of either, and redesigned from earlier models of the Sphinx line so that newer technology could be used so that that less hand work was required..)
A lot of 1911s using an older Browning design, and many guns set up for Bullseye are very accurate. I know, too, that the Army Marksmanship Unit's gunsmiths have been able to take versions of Beretta M9s (sow's ears, to my thinking) and turn them into Silk Purses. Those guns don't have the same Browning barrel/slide connection as the P210.
It seems to me that
if the master gunsmiths, craftsmen and technicians building the newer version of the P210 can get that same level of consistent lockup using a different lockup style, perhaps using newer CNC technology, the lockup method may not be a controlling factor. Can they? Do they?
I've not seen any real performance testing of the new P210 line and if there are such results available, I'd wish someone would share it with us. (I don't mean gun magazine tests or reviews -- I mean serious tests using Ransom Rests by people who really know what they're doing.) That might give us a better idea of just how good or how bad the new P210s really are.
