I didn't check that link before, I remember seeing those, never saw anyone with them (maybe they had the same problem I mentioned). In those days, a lot of badly thought out ideas made it to market. But, a key design difference brings up another problem with the sketched design:
The male end on the production model was not fixed- it could rotate within the adapter. You would tighten the assembly down, loosen the set screws, rotate the adapter, and then lock the set screws once in place. This would only lock the adapter in place relative to the male threading though.
If the threading on the sketched piece is not rotatable, it will need to be indexed to line up with the gun it's attached to (again assuming we're talking about a gun here since it's not mentioned in original post) and even then, may not line up perfectly.
A locking nut could certainly help but, I don't know if it would be enough.