Sorry Illori, but I think when we are obviously talking about skipping multiple versions, (this time the forum being originally based on RC1) I think it's illogical to suggest a more complex procedure not actually meant for updating.
For the end user I think it is easier to keep three things separate; update, upgrade, and reverting to a clean install.
But that being said, if the database is OK and works with 2.0.15, that would work just as well.