Literary analysis: is it a Rorschach Test?

Here is a somewhat edited version of a conversation on twitter between me, AmaliaTD and AvenSarah, both of whom grace these pages from time to time. It began with me retweeting something that might be an urban myth:

Gary: Alfred Hitchcock once helped his granddaughter write a college paper on his film SHADOW OF A DOUBT. His analysis earned her a C.

AmaliaTD: That really doesn't surprise me at all, but it's still hilarious.

Gary: It shows how totally overdone is critical analysis. Somewhere in the afterlife, Shakespeare is laughing his head off.

AvenSarah: Or that authors are not experts in their own work. ;)

Gary: That's the English Department rationale for why literary criticism should be taken seriously! I confess I'm not convinced. There's the Rorschach Test Effect of people seeing things in a story that the author certainly didn't anticipate, but that's identical to seeing interesting shapes in clouds. The clouds didn't intend to look like a bunny rabbit.

Your turn! How do you feel about all those meaningful essays you wrote at school? Feel free to tell me how totally wrong I am.