Thank you. The initial list was from blogroll.org (mentioned in the about page, and I emailed the person who built that). From then on, I review every submission that happens via the form.
replyThe scheduler flags blogs that fail and doesn't try to fetch after a few tries. I'm still working on an effective way to re-review and prune. Open to any feedback.
I'd say a periodic job that looks at the last update of all your blogs, and removes those that haven't updated in over a year would be generally agreeable.
replyIf you want to be exceptionally kind, you can also email the submitter and tell them their blog has been removed due to inactivity, so they'll remember to submit if they start blogging again.
I suppose my dream would be that the protocolization of this from back in the day gets revived in some way. Like a google pagecrawl style index built up from blogrolls (though I don't know if the blogroll itself was ever literally protocol-ized), combined with some checking of RSS feeds for activity. Or webrings, or something else.
replyThough in some respects these are less smart than what you're already doing, but I would like to think there's an elegant way to make an index emerge organically to minimize the editorial burden of any one person.