What IS goalie interference?

Tim Peel, Retired NHL Referee, gives us perspective on what it’s like being an NHL ref and what he thinks about some calls the Canes have recently encountered.

What was it like before there was instant replay? How does a ref determine whether or not it’s goalie interference? Does Sydney Crosby get all of the calls? Are there more or less calls in the NHL playoffs? Some players have reputations for embellishing, does that impact how the refs make calls during a game? As a ref, how did he feel about the Carolina Hurricanes?