Actually it does somewhat the opposite.
What it does is changes the front O2's drastically then watches the rear to make sure it changes slowly but does indeed change. (thats how it'd respond if there was a cat in there)
The test doesnt stop if you have an emulator. It either needs the O2's to change quickly (bad cat) or slowly (good cat).
By that logic, Silver's solution should work.
More traditional methods include: run a cat, have the cat test itself deleted or put in one one or two of those cheaters which are basically O2 bung extensions of some sort. I believe TeeWX has more info on those cheaters.
