I remember the episode where they invented the idea of a "residual haunt" as opposed to an "active haunt." They even went so far as to say the phrase: "we have this theory that..."
Then, about a season later they said: "it's a common theory among paranormal investigators that there are basically two types of hauntings: the residual and the active."
The thing is, while they do legitimately debunk a lot of stuff, the debunkings are often just as much hooey as their theories. For example, all of the stuff about EM and how it affects people - you weren't being watched by a ghost, you were just too close to the space heater elements and they were affecting your mind! :rofl: