I've seen the cross domain canonical not work at all in my test cases. And an interesting point was brought to my attention today. That point was that in order for the canonical tag to work, the page that you are referencing needs to have the exact same content. And that this was the whole point of the canonical tag, not for it to be used as a 301 but for it to consolidate pages with the same content.
I want to know if this is true.
Does the page you reference with a canonical tag have to have the same exact content?
And what have been your experiences with using the canonical tag referencing another page on a different domain that has the same exact subject matter but not the exact duplicate content?
