OP's link is 404ing and moot's won't connect at all for me. There's no way HN took down 4chan. Anyone have additional info/a mirror?
And you need to disable HTTPS Everywhere for blog.4chan.org since Tumblr doesn't support HTTPS :(
Edit: I just noticed moot's comment about disabling HTTPS Everywhere. The XML has an exclusion for "status" but not "blog". I'll send a pull request.