We used EB Welding for manufacturing jet/turbine engine parts, and two metals can be completely joined together.
Not saying that this is a superior method of manufacturing 1911 frames, I just don't see a downside to it.
Colt experimented with this in back in 1939 and brazed the halves together but it was never adopted for production.
Electron Beam welding is a far superior method of joining the halves, I don't see any downside to this manufacturing method.
There are a few at our club that fall into this category. I’ve asked this question in the past with Mike, now with new leadership it just might happen.