Oh heck, everyone's a rottie expert these days, even those who have never owned one.
I remember one time leaving a pet store, the person in front of me had a very well-behaved and friendly rottie with him. On his way out the door, a family of 4 was also coming in, the father of that four put out his arms to shield his family and shoved them back up against a wall.
I started laughing at him saying as I passed "way too much drama you got there dude, way too much drama" What a twit.