I know that deleting blogs can be a pain, and if you are writing for a living, having a non indexed profile of articles can be handy to show prospective clients.
This is what I do. Set up your blogger blog to NOT index when you build it, and use a dynadns or other domain redirect when you use copyscape. Go easy on the short url services that are most popular, or you will waste your time. Got crap domains? Use them.
I do this for each large writing client I have. I had one stiff me, so I set it to index, and DCMAed HIS clients (LOL, by using copyscape again) (I was a subcontracted) with proof of creation time listed for every post. I use them for portfolios so as not to send to actual client sites, and like I found, can be a rather good way to at least keep your content if you do not get paid.
Lesson? If you do not pay me Adsense will, thanks for the free SEO research...