Evolution is spot on.
Could you shoot a slug through a MOD? Yes. Would it do any damage? Maybe, maybe not.
The way I look at it: Better safe than having to get a new barrel for my M4.
My M4 came with the factory supplied MOD choke tube. I bought a Cylinder choke and can shoot everything through it.
John Doe, you are not being a nuisance at all. You have come to the correct place to gain knowledge about your M4. All here are fans of shotguns and fanatics about M4’s