Normally hopeless NFL fans in Michigan and western New York can now reasonably ask a question that hasn't come up in years—let alone in September: When do playoff tickets go on sale?

While the football world struggles to comprehend that the Detroit Lions and Buffalo Bills are both 3-0, here's something else to get used to: They're probably going to the playoffs. Since 1978—the year the NFL went to a 16-game season—76% of the teams that started 3-0 ended up making the playoffs (excluding shortened seasons).

Granted,...