I know people who work at major studios without degrees and they're very good at what they do.But, without a 4 year degree from an NYU and the internshps you are gven, the studios will not take a chance on you.
To be a good editor, just for example, it just takes practice. If I wanted to be an editor I would definitely choose to just jump in and start working at the bottom.
I majored in Broadcasting, although I went to college to have party and have fun and because going to college was "expected of me". But in retrospect I can hardly remember anything useful that I took away from my Broadcasting classes. The only classes that were worth my while in college were two advanced English classes. That's about it. I wish I had at least studied law or something during those 4 years.
Watch "the College Conspiracy" on YouTube. Worth a view.
A friend of mine works on a lot of USC grad films and reports that a lot of these students spend a fortune on their films and by that time they appear really fed up and angry with the business.