I'm pretty sure there have been plenty of books and documentation on regexps at least as far back as the 90's. I distinctly remember O'Reilly books on the topic, that far back, to be specific. For a certain generation at least, we haven't been waiting to be able to learn them. It's out there. Though having additional angles of approach is not bad.
I never liked the O'Reilly approach. At one point I had read 20 of their books and never felt like I learned anything. Some people can learn from references, but I really prefer Zed's "hard way" method which feels a lot like the Programmed Learning methodlogy (http://en.wikipedia.org/wiki/Programmed_learning).
Understood. Technically there has always been a harder way available to all of us. You acquire a book or some other documentation. Then you sit down at keyboard and write the bare minimum code/syntax to test if you understood how some things work, or just play around it. The terminals on Mac, Windows, Linux have allowed us to do this for decades, as far back as my own childhood, to give one example. So yeah, I think the "hard way" is good, and iterative feedback and experiment is good, and that's been available for a long time even without Zed's things. I'm still learning new things even in the last few days, using this approach, except without some third-party playbook I have to follow. Learn Redis the hard way? Download it. Install it. Start it. Enter client. Type things. See what happens. Repeat. This is fairly obvious.
Agreed O'Reilly is probably more famous for their "completeness" rather than effectiveness at teaching.
