What a condescending piece of junk. It serves absolutely no other purpose than to make programmers who do grok everything mentioned feel good about themselves.
Worse yet, programmers who could actually benefit from an article like this (i.e. programmers who shouldn't be programmers) won't understand it. E.g. "(Functional) Creating multiple versions of the same algorithm to handle different types or operators, rather than passing high-level functions to a generic implementation" - a bad programmer won't understand what is meant here, so he will simply skip over it and not get the hint.
Finally, I find the notion that you can't be a good programmer if you've never really used Lisp laughable.
The actual quote about lisp is: "5. Lisp is opaque to you". I don't think the criterion isn't whether you used Lisp or not. He probably meant: "could you understand Lisp if you tried? If you can't, then that is a red flag".
Actually I found this article quite amusing. I've done almost every single one of the things he mentions. Perhaps these are universal mistakes programmers make as they are learning? Anyway, I am please I'm not the only one.
I think that if somebody just skips over programming-related things that they don't understand, it might be indicative that they are destined to be bad at programming.
Worse yet, programmers who could actually benefit from an article like this (i.e. programmers who shouldn't be programmers) won't understand it. E.g. "(Functional) Creating multiple versions of the same algorithm to handle different types or operators, rather than passing high-level functions to a generic implementation" - a bad programmer won't understand what is meant here, so he will simply skip over it and not get the hint.
Finally, I find the notion that you can't be a good programmer if you've never really used Lisp laughable.