What are the advantages of 301 redirects over rel=”canonical”?

In the 2009 rel=canonical video, you suggest using rel=canonical when we CAN’T use a 301 redirect. But 301s hurt performance; they require browsers to make an extra round-trip to my servers. Shouldn’t I use rel=canonical everywhere, instead of 301s? Dan Fabulich, San Francisco, CA Have a question? Ask it in our Webmaster Help Forum: groups.google.com Want your question to be answered on a video like this? Follow us on Twitter and look for an announcement when we take new questions: twitter.com More videos: www.youtube.com Webmaster Central Blog: googlewebmastercentral.blogspot.com Webmaster Central: www.google.com