I just asked the guy. He had self-taught himself programming on his own for a few months prior to attending the program, but attended in part to make a career change (had done startup biz dev / operations / whatnot prior.) Maybe that counted, or maybe they just tightened the restriction since then.

That said, this was spring of 2012. I'm sure Hacker School has changed a lot since then! Suffice it to say he's a fabulous programmer now. :)