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So I did. But after some tries I gave up and did something else. As writing this post in Notepad.
These are my advice to Google and the Blogger development team:
#1 Separate the blogs from the Blogger administration application. They should not run on the same platform. If needed, blogs are so simple that they could just aswell be generated as static HTML pages. I can live with the administrative application being down for some time, but the public blogs should be running with no less than 99,99% availability.
#2 Communicate via a static HTML page what is happening. Do not simply provide a 502 Server Error page that says nothing of value.