Bsteele, your thought was correct, the faux hammers/cocking levers on the Moore and Grey do pull the firing pins back when placed on half cock. This eliminates the possible interference from protruded firing pins when opening the gun, and the cocking levers prevent opening the gun until it is on half cock and firing pins are out of the way. Here's a picture of the inside of the Moore and Grey lock, Grey patent.

[Linked Image from i.imgur.com]

http://www.bakercollectors.com/