[Plugin: Similarity] Very odd

I’ve tried about 7 different plugins (including this one) that are supposed to return a list of posts with related tags. None of them return any result, even though for testing, I have nothing but posts with the same tag, in the same category, and by the same author. The posts are private, some plugins have settings to accommodate that, others don’t. Regardless, I’ve had no success with any of them. Then I found this code:`

[Code moderated as per the Forum Rules. Please use the pastebin]

And it works. Go figure!

http://wordpress.org/extend/plugins/similarity/