Only take Corsi as a measure of Haggs play when Hakstol asks him to become a puck moving Dman. That is not his game and should not be his game. He may be able to develop into a 2-away if he becomes a big part of their future, but they should keep him as a defensive Dman.
Hagg, right now, doesn't have the ability to puck handle in the ozone. He will get in trouble if he tried to do that at the blue line because if he has a giveaway, his speed is too slow to catch up. He should really only be dropping the puck in or making seem passes to players down low which he does now. Andrew Macdonald has the worst Corsi on the team and that may be due to Hagg being his partner, but neither player should be counted on to generate offense since that's not their game.
Hagg is great in his own zone. That's why Hak loves him. He's reliable in front of the goalie and in the Dzone. Not many goals happen when he's on the ice which is why his +\- is so high. He blocks shots, separates players from the puck through hitting/stick checking/ and zone covereage by disrupting passes. He will be solid in his own zone and has shown that which is why he gets PK time.
He is not a 4th forward, he won't produce like one, he won't play like one, so to all the people that make comparisons of his game to that of a 4th forward (Sanheim and Ghost) you cannot do that because he doesn't play that way. You can compare their defensive game because that is their position. Corsi is for who generates offense. Hagg isn't supposed to generate offense... he's supposed to suppress opposing offense which he does real well.
