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-- Google SEO News and Discussion
---- Having Google +1 button on a page will override robots.txt blocks!
indyank - 6:18 am on Sep 3, 2011 (gmt 0)Thread source:: http://www.webmasterworld.com/google/4358033.htm
I don't think canonical tags are a good solution to this issue for several reasons. Moreover, they are not widely used and they are just hints for googlebot.
robots.txt should take precedence over anything else.
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