A Stealth Parody is parody that comes across and purports itself to be the the real thing, often the proprietors of a self parody website or group will flat out deny that they are in fact a parody.
Stealth Parodies are often created by people with completely opposite views that the alleged parody contains, and the parody has been created to discredit the group that holds the opposing views. Organizations such as Conservapedia and the Flat Earth Society are often.
The world is flat? You don't really believe that you're just a troll stealth parody.