Good job.
Your post is sensible and I think that you are correct in your assumptions that putting 9 people working security to watch for someone taking a rock or 2 in their pockets is an expense that would increase the all in cost of mining an ounce.
Then our friend will be whining about how much the costs are and that they should be doing everything that they can to bring those costs down.
This guy is talking circles and more circles. We just need to ignore him.
He is just as annoying as 5 bucks by friday.