Blogspot domains and ranking

Some blogs on blogger / blogspot appear with several top level domains, as shown last week.
What seems not to work though, is ranking with these urls.

I found some blogs which have a few results show up in SERP, but even German blogs had more results with the .com domain than with the .de domain, although they showed up with a de domain when I searched for a generic blog.

I guess to better understand why this happens, it would be necessary to check what was the start domain sites used, and what are signals that could trigger these results.

Any ideas?