As it ever will be, much as it may pain our moral sensibilities.
Re: CoD - I loved it. Laughed my ass off. Absolutely a big fan of creative approaches to getting cheaters to tell on themselves. I proposed something similar to my team when we had a problem with players manipulating the position of objects in the world so they were directly in front of the player: add an object of the same type inside map geometry and attach a "kill volume" to it, so it was like a landmine. Move the object in front of the player and they instantly die :P Wish we'd done it but couldn't get the level designers' time to implement it unfortunately
One we did do though: back when the product I worked on was on PS3 one of the big problems was hacked consoles spoofing platform entitlements (the thing that tells the game what purchases they should have access to). So we added an entitlement that couldn't be acquired in any legitimate way, and gave you a specific item in game. Then we just checked player inventories once a week for anyone with that item and banned their account, their console, and any account that played on that console for a meaningful amount of time. Did the same thing with an item you could only get to by clipping through geometry. Even put the word "intrusion" in the item's name haha.
The cheats are so technically complicated at this juncture that the creative stuff is often the most effective. I mean, people are literally voluntarily installing hypervisor rootkits to run the cheats, so they can talk to their drivers below even the kernel. It's so hard to come to with technical solutions to a problem like that that doesn't wind up costing massive server processing power to validate every input.