Probably the best solution is to have a "posted by" (editor name) and a "submitted by" (user name) like Slashdot. Alternatively, an "edited by" tag added to anything changed after submission.

I second that, but I think editors want to stay anonymous. Just adding an asterisk next to edited titles would be sufficient.

I'm not sure I understand that explanation.

So we share the same title for each link (yes, we do), but we see different comments?

No, we don't: if there's a ridiculous/obnoxious/puerile/etc. comment posted, we all share that, too.

Why should the editing policy for titles be different from comments?

He may have meant that different users should give a specific submission the same title, one without spelling mistakes and bias. So if a user titles a submission with spelling mistakes or bias then it would be reasonable to edit the title to the correct form.