The first link is about both Japanese and Chinese.

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/

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).

https://www.youtube.com/watch?v=sJNxPRBvRQg

With kana there's really no better way to do it than just writing it.

Like a certain Japanese guide puts it, "write it 100 times and drink some beer".