To watch "The D Train" is to imagine that co-writers/directors Andrew Mogel and Jarrad Paul must enjoy standing at the back of the auditorium watching their movie, waiting for the audience to catch on that "The D Train" isn't the usual buddy comedy. In a full house, half the audience will be shrieking and the other laughing, both in surprise. [...] one might easily wonder why Jack Black chose to make what, at first, seems like a routine little comedy. [...] Dan is on a par with the role Black played in Richard Linklater's "Bernie."