Not very. They typically either lose, lose so badly that they are forced to rewrite their contracts, or claim victory after being forced to pay the employee for

Not very. They typically either lose, lose so badly that they are forced to rewrite their contracts, or claim victory after being forced to pay the employee for the time they'd be prevented from working. The problem is, if you're an individual, it's a huge pain in the ass to duke this sort of thing out. You might even get unlucky in a cut-and-dry case, simply by virtue of not having much money to spend on it.