So you would have actors handed a gun in the scene stop to check the ammo and then have editing and digital effects remove that in post? That's insane.

Obviously there's a point past which you don't check it any more. That's why always checking is "basic" firearm safety and not "movie production firearm safety".

I'm basing what I wrote on this article where the armorer defense says there was a live round found in the dummy round (not blanks) box. It would be pretty dumb for them to make this argument if the dummy rounds (not blanks) were color coded and easily distinguishable since that would put even more blame on the armorer.