I have to say you are one unlucky S&W guy.
Something strikes me as very strange here-
I'm going to need some help here.
I have not been inside a gun with the internal lock.
I HAVE been inside several hundred S&W's before the lock.
I have disassembled them, repaired them, rebarreled them, timed them, done action jobs, fitted DA sears, fitted ratchets, etc.
It is safe to say I KNOW how they work.
Are the new guns that different?
You CANNOT open a cylinder on an old gun with the hammer cocked.
So, please explain how "he removed the cylinder".
That would be a very difficult task.
You cannot remove a cyl that is not open. Again, you cannot open a cyl on a cocked gun.
I could do it on an older gun by popping the sideplate and removing the hammer, but I would really hate to be doing that with a LOADED, COCKED gun at a public range. (does anyone know how sideplates are removed?

)
Am I missing something here?