Joel Spolsky thinks blog comments are evil

In a recent post Joel Spolsky agrees with Dave Winer regarding the misuse of blog comments:
"to the extent that comments interfere with the natural expression of the unedited voice of an individual, comments may act to make something not a blog"

Joel furthers the idea with his thoughts:
"You don't have a right to post your thoughts at the bottom of someone else's thoughts. That's not freedom of expression, that's an infringement on their freedom of expression."

He goes even further in regards to anonymous comments:
"Thoughtless drivel written by some anonymous non-entity who really didn't read the article very carefully and didn't come close to understanding it and who has no ability whatsoever to control his typing diarrhea if the site's software doesn't physically prevent him from posting."

I may agree with Dave's original idea (as I understand it) that both commenters and bloggers would be better off writing in their own blogs. I have been trying to convince a friend slightly addicted to writing comments to news articles to start blogging instead.
But what both writers seem to forget is that comments are also used for trackbacks, and in this sense they "throwing out the baby with the water", since no one will ever read those comments-inside-blogposts, unless google ranks the commenter's blog fairly high.

It may also be related to the popularity and/or subject of the blog, but I don't see anonymous comments as the evil Joel compares them to. I have read many blogs from Jeff Atwood, Scott Hanselman, Phil Haack containing meaningful and entertaining comments, some of them anonymous. Someone may have great ideas and the desire to express them, but no desire to open a blog, and you can force that person to start blogging.