To paraphrase a line spoken my Harvey Keitel in the movie U-571 as the American crew took the U-boat to 500 feet below the surface, "Those Krauts build a hell or a gun (boat)".
https://en.wikipedia.org/wiki/U-571_(film)
A London best rifle or gun is arguably the finest sporting arm in the world. They were also meant to be returned to their makers after the shooting season for inspection, tuning, tightening, and if necessary refreshing. Correct me if I am wrong but didn't H&H use Mauser bolt actions before and after the World Wars?
American sporting arms, at least until 1963, were made to last a lifetime without need of anything but cleaning. There were working arms, many of which reside in my gun safes still ready to work.
German sporting arms designed by German engineers and manufactured by German craftsmen and machinery are like American arms but of more intricate design. Dollar for Dollar, I trust German or Austrian engineering far over British for most any type of machinery including firearms.
The Greener Crossbolt while of British design, is used by Heym and Merkel to lock their actions. It may not be the prettiest mechanism but it is not going to allow the action to open if a round develops too much pressure. By design, it will stabilize the action as the molecules take advantage of Youngs Modulas, "everything is a spring". The less elastic an action is, the less chance of plastic deformation (permanent warping out of shape) where it comes off face.
https://en.wikipedia.org/wiki/Young's_modulus
The above stated, H&H actions may come off face for many reasons; over pressure loads, lack of cleaning and lubricating the action, and what I suspect, materials like the steel used that may not of been of the same quality as used by Heym.
German or British engineering? If I were going to buy a sports car that I would drive hard for 200,000 miles over ten years, like I have my trusty Ford F-150, it sure as heck would not be a Jaguar, as beautiful as they are. No, make mine a BMW or maybe a sporty Audi. After all, those Krauts build a heck of a machine!
The above is my opinion. Yours may vary...