hyblog's posting has been improved to reduce the need for manual addition of the double @ separators.
The first post of the day is added as normal. After this, a new '+' button appears in the top right corner when logged in – click this to show a new post form. The post content will be automatically appended to the day's file with separator and time added.
You can still double-click the post contents to edit the whole lot but, at least, posting is a lot simpler.