When I have 'bookmark to local folder' checked in the options, and I have multiple tags against a bookmark then multiple bookmarks are entered into my local folders.

This messes up the organisation of my local bookmarks and other firefox extensions I use to navigate them (tagsifter).

In creating multiple folders to represent the tags and putting duplicate bookmarks in the different folders you are breaking the organisational structure this is built in to firefox bookmarks. Why not just put a single bookmark in the tag folder for the first tag? Or develop your own tag extension that allows for sorting by tags rather than creating a kludge?

The is an app killer for me. It's a shame as there are many other features I really like, especially highlighted annotations.