My wife was fired from a job, and she signed a non-compete so she couldn't start her own business under those limitations. She started another business anyway, promptly got sued, and promptly won and had her legal fees paid for by the defendant. It was first court case I ever sat in for, and it was interesting. At the end the judge told the defendants right out that if they appeal, they would lose again.
My wife's lawyer simply argued that it was too onerous for her to not be expected to want to practice again and that she not only would not take information and private practices to her next job, but that she in fact had developed some of those and they were not the sole ownership of her bosses. I guess a non-compete is one way to stifle innovation or free enterprise. Thank god it's gone.