I was surprised to learn that the search API returns hits on usernames when they appear outside of the post/comment content.

I'm looking now to see if there's an easy way to filter around it. I've also been emailing with one of the ThriftDB guys and I'll ask him as well.

If not, it'd be very difficult to filter those out because I'm not currently (nor would I want to) retrieving all the matching items, just the number of hits.