It becomes a liability for negligent discharge under stress. The trigger pull when it is single action is light enough that you could accidently discharge it if you are startled. Other than that I would put no faith in the OMG he cocked the hammer court room reasoning.
Basically ignore almost everything you've seen in movies and TV, or many old-timers.... Don't pick up a gun and go to the trigger, twirl your guns, shoot from the hip, hold your bottom hand in a teacup grip... and learn to shoot double action only.