It was a while ago when I last tried, and I did wonder whether I was mixing up experimental and testing in my mind as I try and recall the details now, but I can try again and see if there's any success.
People being able to try out testing would be one fewer reason to freeze unstable, I think.
Posted Jan 16, 2013 15:58 UTC (Wed) by cortana (subscriber, #24596)
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It's possible that there was a bug in one of the packages that comprised testing at the particular time you installed it, and that may have prevented debootstrap from finishing. Such bugs are pretty rare though--they usually get noticed during the 10 day waiting period between packages entering unstable and transitioning to testing.