When Roy Boy's son became a driver, the dispatchers pestered him for what nickname he wanted. They were probably thinking along the lines of Roy's Boy. After about a week, he came up with Tiberius.
Turns out, Brian T. aspired to be an actor. And it turns out that Tiberius was probably played by Shakespeare himself, in a play called, Sejanus His Fall, first performed in 1603 and ran through part of 1604.
Everybody thought Roy Boy was a cruel enough man to give his son a middle name as off the wall as Tiberius, and let it go at that, and that's what we all called him.
Then, a couple of days ago I ran into Roy at the supermarket, and asked him how Brian was doing. He said that Brian was a leading actor locally, and had performed with every theater company in town, doing lead roles. Tiberius indeed.