That question is posed by Bryan Caplan on the signaling value of education, here, via our reader Mike's site, here. (Thanks, Mike)
My perspective on the topic is that educational signaling, like dressing well, good manners, or possessing a good pedigree, will only take you so far in life - maybe to your first or even second job, but it alone will not lead to a happy and productive lifetime white-collar career or careers. That requires fortunate combinations of personality traits including social skills, a bit of dignitas, leadership skills, savvy judgement, a quick penetrating brain, good ability to assess others, a cheerful but forceful disposition, integrity, good intuition, etc., of which many folks lack at least one element. (I lack more than one of those, which is why I am a Partner and not an employee. Like many Maggie's Farmers, I am not fit to be an employee but I am a darn good tough but caring boss: if you don't bs me, I'll be on your side when you screw things up - which you will.)
After the first or second job, the only real value of fancy academic signaling is social. The old school tie networking is highly over-rated these days (except amongst the Dartmouth Gang and the prep school kids who help their own tribe no matter what. Yalies? Not much anymore, since Yale went psychotic).
When we interview at my shop, we partners interrogate the candidates first, and glance at their resumes afterwards. We like to size a person up. Get the cut of their jib. We do not like slick, and we do not like negativity. We have a soft spot for vets and/or people with a strong sport because those things matter to us. We see through bs like a laser. We enjoy dry humor as well as raunchy humor, and are bored by conventional thinking and ordinary "nice" personalities. We try to decide whether this is a person we'd enjoy and benefit from having around every day, somebody we can learn from - and have fun with at dinners and parties. We like to be surprised, and we enjoy quirkiness when associated with brilliance and creativity. And we are looking for the beef: "Teach me something I don't know about ____"
(Admittedly, our candidates are screened first by our junior people, and how they do that is not my concern.)