I don't HATE, hate Scooby-Doo. It's just a cartoon show. Mind you, it often was a horrible filler between more awesome cartoons during a typical 80's Saturday morning...and I've seen every one of the classic episodes like 10 times...and the plots are ALL the same. But, it's just a show.
No, when I talk about Scooby-Doo, I'm talking about Scooby-Doo Syndrome. It's a term I use to describe a game gone wrong. Usually when a: The GM is tired b: The GM and Players don't communicate well or c: a session of "just winging it" goes horribly wrong. Or some mix of all 3 reasons.
I call it Scooby-Doo Syndrome because it accurately describes what happens. The game starts out with a standard mystery or unknown event. The PC's investigate, and then everything goes WACKY for a few hours, and the resolution doesn't make sense. Or more often there isn't a resolution and the session is called a "Dream Episode" or just forgotten. Embarrassed GM, laughing or miffed players, and you call it a night.
Remember me talking about the trick of using the player's paranoia to your favor? Well, this is what happens when you take it too far, or go way out of your way to go against what they THINK is happening.
So instead of say: The McGuffin was stolen the Bad Guy to raise his dead wife...oh no. He's using it raise a dead harem, or his dead dog. Or the McGuffin is a Red Herring (another Scoobyism) and it's actually a trap to lure the PCs into a murder machine. Or the whole thing was a scam to make people think the McGuffin was worth money and 3 ninja clans are fighting over it now because they think it will give them real ultimate power. Somehow the Decepticons got involved and then we had to become plumbers to sneak into the base to steal the McGuffin back, only our love intrest betrayed us thanks to ninja magic...and demons from the planet Zog. But in the end the BagGuy was actually our land lord Mr. Smithers and it was all just something to make us move out so he can sell the Grotto. He hired the ninjas from Hollywood by way of Chuck Norris, and suddenly there is wizards riding dinosaurs.
Confused yet? It gets worse, but the the problem compounds with run-on plots. Dangling clues and events that the GM forgot about and has to resolve, and loads of strange "Pardon Me?" moments. Que the 60's music, run around the hallways for a few minutes. Call it an episode.
I've had quite a scoobies in my day. Too tired, too stubborn, too silly to see reason and just call it game.
Worse, some of my games became a series of run on scoobies I had to resolve later when I was sane/awake.
So put the dog back in the van and send him down the street. No more old men in costumes for this GM...until I forget the lessons learned one session and suddenly it feels like a re-run.