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How do I become a more knowledgable spectator?(r/nfl)
Take Your Eye Off The Ball by Pat Kirwin
Football Scouting Methods by Steve Belichick (yes, that Belichick).
The Kirwin book is recent and pretty good. Definitely an enjoyable read. The Belichick book is much older and has some outdated formations that you won’t see any more, but it’s still a pretty valuable and enjoyable read.