Soldering the inner ring to the outer ring is very time consuming and I think, you should see traces of solder at the seam?
Because the material of the solder has a different alloy than the ring itself. Why? the melting point of the solder must be lower than the melting point of the rings, otherwise the rings will be destroyed while soldering?...
I have the exact same opinion about two bands theory, I can add that after a close examination (magnification 20 x) none of my 8 SSHr shows traces of a double band construction.
On the other end I was lucky enough to find an italian ring made by nickel in 1930 that clearly show a double band construction even under a 10x magnification.
