You know, it's not a myth. It just requires discipline, and working for a company that doesn't suck. I've managed it for the 28 years since my first child was born. I just decided to start working normal hours. Since I got as much done as when I worked 60+ hours, no one seemed to care.
Is this is really true for most large US companies? What's your definition of large? I've worked for companies with several $100 million in annual revenue, is that too small too count? Maybe you should avoid really large companies if that's the case.