yes! the main header on the Priceonomics blog originally linked our home page, but that left users stranded on blog post pages when they wanted to visit other tumblr posts quickly.
imo a link to your homepage elsewhere is a better solution
We're doing the same thing at MakeLeaps[1].
The logo (which also says MakeLeaps Blog) links to the blog's homepage and to the right we have a prominent link saying "Back to makeleaps.com".
As the logo and link are the only things in the header this works pretty well for our visitors/users.
While designing my startup's blog[1], I looked at a lot of other startups' blogs and noticed that most of them had the same problem the author describes. My solution was to just put a 2 line description of what we do with a link in the blog header, so it is very easy to get to either location.
1: http://blog.tabuleapp.com