Agreed. You have to have thought it through ahead of time and practiced. This is not a one time thing. I routinely take walks at work. Yes, in part just to get up and get the blood flowing again and stay awake. But also to familiarize myself with the current condition of corridors and various public spaces. There are always projects in work, things moving and being stored. I know, day in and day out, where cover and concealment is available.
I also practice moving through my house, clearing rooms silently in the dark - yes with a loaded firearm, with and without the dog. Granted, I only do that when I'm alone, I don't want to freak out my wife. ;-)
I know I know, some people reading this probably think I'm a little off, or I need a hobby. ;-) I have several hobbies, this kind of thing is just one of them.