I'm not sure this was always the case. This blog post explains how to add canonical links pointing to a new site, but when I tried it I discovered that Google has done something that leaves an extra canonical tag in the header. If you look at the template in Blogger, you won't see any reference to "canonical" but if you check the source code it turns up, and points to the URL of the source code.
Why does Google do this? I don't know. But I know how the canonical code is getting added, via this bit of code in the template:
<b:include data='blog' name='all-head-content'/>
The result for me: after manually adding another bit of code to add a canonical link to a new wordpress blog, I found that the resulting blogspot page now has two canonical links: One pointing to my new wordpress blog page, and one to the original blog page on blogger. This surely is a big no-no to Google, and might have a detrimental effect on ranking if the algorithm thinks I am trying to confuse it for illicit means.
I am tempted to delete
|Blogger settings page|