Gentlemen,
Thank you so much for the detailed replies here, and to be honest, I'm somewhat surprised that there are so many differing opinions. My Shadow 2 (S2), is so new to me that I am still familiarizing myself with its subtelties, and it definitely functions somewhat differently than other semi-autos that I own, even those that are relatively similar.
I think the most striking difference is the option for a 'half-cocked' hammer, and to be clear, it 'IS' possible to engage the safety with hammer only half-cocked (I have a photo, but don't know how to attach it here?). You simply chamber a round and slowly lower the hammer with slight pressure on the trigger, and obviously, this then requires a double-action trigger pull, rather than single-action (as when fully-cocked), but that was at the heart of my question.
For starters, the S2 is obviously quite large and heavy, and so yes, it is unlikely that I will ever carry it, but by example, in an immediate personal defense circumstance, I would have no issue with a required double-action pull weight (hammer half-cocked and safety engaged), IF it was inherently safer than single-action (fully-cocked) with safety engaged. I hope that makes sense?
So unless I'm missing something, it seems to me that the question is rather straight forward . . .
Since the safety can be engaged regardless of hammer position (either half- or fully cocked), is one of those options safer than the other, regardless of whether the firearm is actuated via single- or double-action?