phranque - 11:04 pm on Jul 13, 2013 (gmt 0)
When I used a site:blog.domain.com, it supply pages associated with the blog not with the original website.
that's the way it works.
if you want to see the index for your main site you could do a search like:
or if the canonical hostname for your main site is example.com:
as blog is treated separately
if you treat your blog separately (with minimal or no interlinking) then google will also treat it separately, other than the minimal connection of the domain name.
a good example of this is blogspot, where all the subdomains are essentially islands of content with relatively little interlinking.
on the other hand craigslist uses cityname.craigslist.org hostnames which are all interlinked and google probably views craigslist.org as more of a unified site.
Your link to blog.example.com is redirecting visitors to the wordpress dot com domain.
if this is done correctly, there is no redirect - it happens in the domain name resolution where the DNS translates blog.example.com to an IP address.
the fact your blog's IP address is hosted by wordpress is about as irrelevant as your main site being hosted by godaddy (or whatever.)