In all of this palaver one thing tended to be overlooked is that after the decocking, and as soon as practical, the hammer is drawn to the half cock (loading notch) position which frees up the cylinder for rotation. The cylinder is then re-indexed or correctly reloaded with the empty chamber under the hammer.
While this has failed to be mentioned, it is the next important step.
To be sure, a transfer bar equipped revolver will require no further indexing.
Scenario: The gunny has fired one shot from his Colt/Three Screw Ruger/Uberti/Pietta/Remington revolver, and immediately cocks the grun for a follow up shot, but finds it is unneeded. Satisfied that one shot has done the job, the shooter then eases the hammer down. Then draws the hammer to the half cock/loading notch, and correctly re-indexes the cylinder. Then holsters the gun.
Bob Wright