> Or do you think a handful of interviews can give a more thorough evaluation that 8 years of secondary school + 3-4 years of technical college/uni + however many years in the workforce?

Actually, I do. I think that uni grades are mostly uncorrelated to real-life ability, and I think that there is a class of employee that's really good at looking good regardless of actually doing well. So his coworkers would say that he did great. Getting stuck with that guy really sucks. Not to mention that most employers are so worried of being sued that at best they'll say "I can confirm Joe worked here from 2011 to 2014"

Work experience yes, school wise no. Unless you are in one of the top 3 CS schools in the country and graduated top of you class, from experience, school grades have no correlation with ability.

Now, I know work experience is tricky as well (I once interviewed a DBA with 5 years experience that had trouble explaining me how to do some joins in SQL) but is more valuable than university experience.

> Or do you think a handful of interviews can give a more thorough evaluation

Yes, when done well

>3-4 years of technical college/uni

College performance (good or bad) is no predictor of how good you'll be as a developer.

>years in the workforce

Not all companies are the same, not all departments in big companies are the same. Managing to work for Bob in XYZ for 10 years and Bob loving you does not mean a) you're any good b) you're suited to a job with Jane in ABC

>secondary school

Are you serious?