That is the key number here. And that was just to get an interview. He got 6 offers from those 70 interviews, which is over a 90% rejection rate, despite some pretty good credentials in his background.
Personally, I go the other way. I send out resumes selectively, and run closer to about a 30% response rate. And In my entire career, I've only ever NOT gotten an offer twice. Not because I am some extremely special coder --- I'm not. But because I take some care in selecting who I talk to in the first place to make sure we're a match before even getting that far.