The whole issue of lockup in a revovler was overstated. The important thing is that the cylinder be as rigidly locked in position as possible at the time of firing, This means the hand (or pawl) locks the cylinder in conjunction with the cylinder locking bolt and holds the cylinder in perfect alignment with the barrel at the time of ignition.
Smith & Wesson placed a third lock in the crane area on their New Century .44 Special revolver. The British tested this prior to purchasing S&W revovlers during WW I and found it unnecessary in practical use and eliminated on their purchase contract. Subsequent S&W revolvers eliminated this as well.
The lock at the yoke is beginning to pop up again, however.