Isn't this illegal? Discrimination laws.
It's not like he's refusing to hire people of color or Vietnam veterans or even transsexuals. (Edit: I realize it might sound strange, but there's a legal basis behind that ordering it's not just my preferences :-)
He's refusing to hire certain resume' histories arguing that it is professionally relevant.
Second, he is creating a hostile work environment for his own employees who may feel differently about the case, or who have come from companies that collapsed as he is expecting Yahoo would.
Hostile work environment? Meh. Sure maybe somebody could bring a suit, maybe they could even have a chance at winning if he was beating people on the head with it every day. But I doubt many startup execs would worry about it to the point they would let it censor their behavior.