He's mostly talking about Kanji from what I can tell. Learning Hiragana is probably a big different. It takes about a weekend and helps with pronunciation. Everybody is different, but I found it useful to at least know about...
I agree, I'd recommend learners to learn kana because you can learn it in a few weeks (as opposed to many years for kanji, and even after that many years, people - including natives - don't remember them very well).
I think Mair's advice of not focusing on the script is valid.
Look at Kanamoji-kai for example (if you can read Japanese):
http://kanamozi.org/