What made the Edmonton Oilers' penalty kill so strong this year? Strong goaltending, strong personnel, and consistent and aggressive tactics designed and executed to funnel attackers away from the middle of the ice and into the corners and behind the net, where defenders could then engage and more easily strip away the puck in one-on-one battles. That's the summary I got in a lengthy interview with Edmonton Oilers associate coach Jim Playfair, who generously agreed to take on the job of educating one mystified fan (me) about the nature of Edmonton's PK success in 2019-20.