When college isn't hard enough

I.
Something seems backwards about the signalling effect of colleges to employers. Ideally, colleges want two things: a low admission rate and a high graduation rate, especially the former.

It is very difficult for employers to project how a potential employee will perform, so they use college degrees as a signalling method. If it's really hard to get into Harvard, they must be exceptional.

However, this tells us exactly nothing about the quality of a Harvard education. 86% of freshman will graduate in four years. What about Oglala Lakota College, which has a 2% graduation rate? How exceptional do those handful of students have to be? It's hard to tell since it has a 100% acceptance rate.

Either way, isn't a low graduation rate a better signal of how difficult the experience is?

II.
For those who can't get into a low acceptance rate college, a better way to signal to employers might be to do something else that most people cannot do. Design your own app or website. Successfully run a small business. Build a combustion engine. Hell, ace a few MOOCs at Ivy League schools.

Imagine you're an employer with a stack of job applications for an entry-level position. They all have young graduates who went to the same schools, were president of the same clubs, and volunteered their spring breaks in the same third world countries. They also lack the hard skills to do the job, but that's fine since it's entry-level and you'll teach them anyway.

Then one resume comes from a student without any of those credentials. They graduated high school, then trained for a year before successfully climbing Mount Everest. They pledge to apply the same grit and determination to learning to crunch numbers for your firm. You don't know much about the other graduates' college experiences, but you know how few people have climbed Mount Everest. Is this a better candidate?

Maybe all the traditional signals—SATs, GPA, volunteering, extracurriculars, class ranking, internships—are becoming anti inductive; everyone does them now so you no longer stand out.

What if we told kids to do something demonstrably difficult, that most of your peers cannot/will not do, and it makes you stand out? Isn't that a better signal?