True, but the "Magnificent Seven" was one of the first (if not only) examples of using two hands on a revolver. "That was the best shot I've ever seen!" "No, worst - I was shooting at the horse."
I shoot "Frontiersman" in CAS simply for the challenge, right gun right hand, left gun left hand - simply because I can. Acquired the skill from IPSC and IDPA.
A while back someone posted a US Army training film on the use of the 1911 and surprise, surprise, there was a segment where the shooters were using two hands!
Fro the Cavalry point of view, managing a horse with one hand necessitates shooting with the other.