“But as good as ‘FBDO’ is, it does run into the serious problem of the timeline from approximately 10am when Ferris picks up Sloane in Cameron’s Ferrari and they head for Chicago, to 6pm when Ferris barely beats his parents home and jumps into bed.”

Via thingsmagazine.net. See also Marxist Overtones in Ferris Bueller’s Day Off and Ferris Bueller: An American Hero.