Karl, Nice theory based on the similarity to other Walther designs, but this is a striker (firing pin) design... the pivoting trigger and external linkage shown above is strictly for release of the pre-cocked striker...
I see no provision for the cocking of the striker in a manner than could be termed as "double-action"...
besides, in s striker design... the firing pin would be resting on the primer if the gun were not already cocked, and waiting for the trigger pull to **** it...
NOT a good idea... <img border="0" title="" alt="[Eek!]" src="eek.gif" />
IMHO, in this old engineer/gunsmith's eyes this is a single action semi-auto design.