Ryan Holiday put together an imgur set containing the process of writing a book.
One issue that I have with blogs, twitter or facebook is that it triggers a kind of anxiety in me. Every time when I want to post something I get a feeling of like "is this good enough?", "does this make any sense?", "what will other people think about it?". For me those mediums do not encourage me to write down my honest feelings and thoughts without putting a big amount of time in it.
I want to address this problem in Shimatta but I'm not yet completely sure how to do this. Of course one option is to allow private posts, but I'm thinking more about the public ones.
I think the initial message what Shimatta is and does and how the user will be triggered for writing his thoughts down will be essential to solve this problem. If the user thinks a post will be read by all his friends and hundreds of strangers it will be much harder to publish something instead when a user is thinking "let's write this down quickly for later usage" and not giving a shit if everything is fully understandable or has grammar mistakes and typos.
Another part is the community aspect. Writing down thoughts doesn't require a follower count, like count or read count. Because it doesn't improve the quality of a thought in itself. So the social "proof" pressure can be removed.
The last way that currently comes to my mind to encourage users to post more is to teach them. A strong habit building onboarding strategy is key here. All in all I think it's a problem worth solving and most importantly I think it's doable.