Playing to the crowd

A situation which I'm always looking out for is when a player is approached by a friend who will inquire as to how he is doing. After being updated, the friend will typically hang around for a few hands, standing behind the player who lets him peek at his hole cards.

When this occurs, I have noticed that this particular player may be prone to making some bold multi-barreling bluffs just to impress his friend. I have doubled up on several occasions in this type of scenario.