I've done it, I have figured out why it is that cats *purposely* and *maliciously* attempt to overpopulate and kill fortresses with their advanced Denial of Service attacks on the dwarves.
The truth is....they are in league with the fire imps and their demonic overlords!
While tapping into a magma pipe for my forges the imps went beserk and injured many of my meatshields wrestlers who were protecting my miners. The attacks were viscious and almost all dwarves involved were permenently put out of action due to CNS injuries.
After the channel was completed, I had to seal up the oppening I dug through in order to channel. In the process 2 cats and a mule were sealed away inside the vault. The second the hole was sealed the attacks simply....stopped, the imps gave up and went back into the magma, ignoring the cats, but burning the mule to a crisp.
Obviously the cats are in fact servants to the fire imps, the technical arm of the UCAG (United Coalition Against Dwarves). I have reason to believe that the conspiracy may extent all the way to the glowing pits and possibly even the Dwarven nobles themselves! The nobles are the ones who convinced the dwarves to bring along the feline double-agents in the first place. Sure they might seem like they are harmlessly screwing around with each other, but in fact they are h4x0r5, 0R m4y83 3V3n "5criPt-KiTti35" m4KiN9 0r94ni23d 4tt4CX 0n T3h DW4rv35 5imul4T3d r34LiTY, 8ut TH@ i5 4 c0N5pIr4CY PH0r 4N0TH3R TIm3 (hackers, or maybe even "script-kitties" making organized attacks on the dwarves simulated reality, but that is a conspiracy for another time)