> But in reality if you stick to these rules hard and fast, you'll basically never accept a job offer. That's clearly an exaggeration, but many-to-most of these clauses are in every boilerplate contract.

In the tech industry, yeah, but there are industries that aren't so employee hostile where you can find better contract terms. I'd have to say in my experience, the tech industry is one of the worst when it comes to the malicious application of employment contracts. Apple is especially egregious with forcing interviewees to sign expansive NDAs; the Dilbert cartoon is spot on by making them dress like Apple store employees.