I have been known to plan some thirty or forty posts ahead sometimes.

I tend to write in bursts. So I sit down and plan out what I want to happen, write a single sentence summary for each post, and then set about writing the dialogue in each post. Then I write the description around the dialogue, be it first or third person, taking great care to make it seem as natural and organic as possible despite often having written the descriptions weeks or months afterwards. Writing this way allows me to take advantage of the bursts of activity I have and get much, much further ahead of schedule (often by some ten to fifteen posts) than I need to be.

It probably says more about my penchant for self-contained arcs than anything else because I'm far less meticulous when I'm playing in a game that requires interaction. Either way, it seems to work for me without having become so beholden to the method that I can't write unless I do it.