I read this about ten years ago, so I'm not sure if it was Matei or not. But it sounds like a Matei Classic to me.
Anyway, Mike is talking to someone at a convention when he lets out a big, loud fart. He laughs it off by saying something like, "Woah, the Fart Burglar is on the loose again. I guess my ass let it out on good behavior!" He then excuses himself.
Honestly... not bad. There are worse ways to handle that kind of situation.
He'd say it in the dumbest voice imaginable and would even add the Woody Woodpecker laugh afterward. Imagine your Bames and Mikey Matei says, "Dat's a Bimmy!" as a catchphrase as if you're in a sitcom. Mike eventually escalated this and would say, "Dat's a Bimaaaayyyy" in a high pitched voice, and he would get in James' face while doing it. The final straw was when Matei said it like a broken record: "Datsa datsa datsa datsa datsa" over and over again while getting up in James' face and being as obnoxious as possible. That was it. Jimmy put his foot down.
Apparently, his wife also said it, although she isn't as annoying about it. She apparently still does it. Hopefully, James' kids don't start it. Imagine Bimmy on his deathbed and his grandchildren going "Dats a Bimmy!" as he waits for sweet relief. Jesus.