Does milling the dovetail in front of the RMR mess with the slide’s integrity?

So Im looking to mill my Glock 21 and was considering RMR behind irons cause I think the sight picture looks way less cluttered this way. I asked the company if they provided this option and they do not believe in it. They said: “By cutting through the outer hardened layer of a Glock slide to make a dovetail, they have mounted their sight in the softer steel underneath. This softened dovetail can deform easier and we have seen many students break their rear sights off doing one-handed manipulation drills when they rack their slides using the rear sight as the load-bearing surface.” Which kinda makes sense to me, but Im thinking wouldnt milling for an RMR already expose the softer steel? Anyone got insight on this or experience with sights in front of RMR? Thanks. via /r/CCW https://ift.tt/3cRkDLb