It's worthwhile to the extent that other people can learn from your experience and get to the good oil sooner.

Personally I learned from The Camel book, the Perl Pocket Reference, the Perl documentation, PerlMonks and a lot of experimentation.

Overall I guess I learned most through my interaction with PerlMonks, by asking for help, by exploring other monk's answers to questions, and by answering other monk's questions myself (which often involved digging around through documentation and exploring solutions).

I came to Perl Best Practises rather late and most of the advice I'd gotten elsewhere, but there were a few new interesting ideas even so. In like fashion Effective Perl Programming 2^nd Edition was a recent addition to my library and also mostly covered stuff I'd already picked up, but is well worth while all the same. Both these books are more useful after some understanding of Perl has been acquired, but before bad habits are too set in place.

Well, as far as "worthwhile" goes - as a friend of mine is apt to say, "hmm, that's one of those judgement call things, innit?" :) If you're a linear sort of learner, then perhaps there's some sort of a path to be recalled, which may serve as a guide to other linear learners. Most people, though - at least in my experience - don't learn well that way; it's usually more of an agglomerative process in which certain things stick at different rates depending on what you already know. It's an ever-changing landscape in which you can't predict what will work best, except that throwing masses of (somewhat preselected) information at that particular brain and giving it some feedback via real-world exercises should eventually produce a net gain in learning.

Mind you, I'm only saying this because I've been a professional teacher for 30-some years and studied countless formal teaching methodologies. Otherwise, I'd consider this way too flip of a take on things. :)