I can't speak for Mr. deBethencourt, but if you cock the hammer on these and decide for whatever reason not to shoot, that little nubbin of a hammer can make them a bit sketchy to decock safely, especially after an adrenaline dump.

On the other hand, having a hammer (especially an inert one) adds another layer of safety while reholstering or administrative handling. Considering this class of firearm is often used for deep concealment where it's not always feasible to "look your gun into the holster," being able to put one's thumb over the hammer can be comforting. Finally, doing a rotation check on a revolver before holstering for the day can get you a little extra insurance, reducing the odds of encountering high primer or other defect jamming things up exactly when you need everything to go perfectly. An inert hammer is the safest way to go about this. Sure, it's a belt-and-suspenders kind of thing, but if you CCW in the first place, you are probably used to this way of thinking.