When you consider that a play is actually meant to be performed, understood, and pondered after a two and a half hour time period, a play should really only require one week in school. Take four days to listen to or perform the show, and then a final day to discuss the major ideas. If we were analyzing Birdman (my vote for this year's "Best Picture"), we'd probably follow the same philosophy. I don't see myself giving Birdman quizzes after each half hour scene.
And yet, if we want it to be, Shakespeare is dense. Single monologues and soliloquies can be dissected for hours. Long forgotten allusions, subtle mistranslated puns, and biblical imagery are lost on the cutting room floor as we inhale plot details (which can be convoluted enough) and ignore the hidden subtleties. Today a student asked "what's going on in this big paragraph?" and while I initially wanted to answer, all I said was "he's saying Macbeth did a good job, nothing to advance the story". I was accurate, but an entire page of the play is now labelled filler when in fact we could find a class-worth of debate...if students were game for it.
To be fair, every work is like this. All novels could be analyzed over the course of an entire college semester if we really needed to but sometimes the big ideas are more important. With Shakespeare though, the struggle to learn the plot is much more advanced than other works, so the disconnect between stuffing ourselves with plot, and savoring the imagery, is much more pronounced.