Writing strategy and 'osmosis' through exposure to writing (ie. input)

Over in the LingQ Twibe playground @skyblueteapot wrote about her brilliant strategy to super-boost her writing ability in foreign languages (she certainly doesn’t need a booster in English, grumble, grumble, grumble).

I noticed that I tend to rely on osmosis of sorts: by following the forum posts in Portuguese, Swedish, Italian and Russian, coupled with judicious use of Google, I seem to have developed a knack for deciphering a lot of text without any work on the languages.

This approach, unfortunately, does not work for me for that most intriguing of languages, Japanese. Nor does it, unlike Helen’s approach does for her, help me to produce output, at least for now.