That is about sealing off the b-c gap for use with a silencer. The OP was mainly concerned about escaping gas limiting the ways in which a revolver can be held. I guess that solution would work in any case, but would be expensive.
There could be an easier solution, though, if any company would do it. That would be to machine a flange around the front of the cylinder like the old Iver Johnson Sealed 8. They had to cut a notch to allow the cylinder to be removed because the gun was a solid frame, but that would not be needed with a swing cylinder revolver. Of course, the cylinder would have to be without flutes, but some folks like those anyway. I don't know when/if the gas would cut through the flange, or if it would.
Jim
