(I have this funny feeling, after writing this email, that it is the sort of email likely to be misused in some fashion as a WP:JIMBOSAYS fallacy. This note at the top serves as notice that anyone citing this email as setting down policy on Wikipedia is being a goof. I am just discussing and thinking here and trying to be helpful.)
Will Beback wrote:
I believe that when an editor on Wikipedia gets into a dispute and uses their blog as a weapon in that dispute, then that the blog is no longer a suitable source for Wikipedia.
While I could perhaps agree with something in this general area, I think this statement overreaches significantly.
First, blogs-as-sources is already a tricky topic, but there are of course cases where a blog is a legitimate source. For example, if a well known person blogs in response to a media controversy, that particular blog post can be quite valid as a source for a sentence saying "In a post to his personal blog, John Doe vigorously disputed the allegations put forward by the New York Times."
Now suppose that same well-known person, in a completely different matter, gets into some kind of squabble with a Wikipedian and uses their blog as a weapon in that dispute. In some extreme cases (death threats? libel? we could discuss...), there could be a reason to delink the blog everywhere. Or, in case of a redirect to an attack page, there is absolutely a reason to delink the blog (because the link is no longer valid).
But in general, it seems to me that a non-libelous perfectly legal rant against a Wikipedia editor would not justify removing an unrelated article space link which would be valid otherwise.
--Jimbo