I actually had originally done that, but then I realized that if we ever change a collection name, historical migrations will stop working. This was why I had the discussion in IRC yesterday about how our migrations really should hard code everything, including the collection names. I believe you said that you were in agreement about that - perhaps you didn't realize that I was also referring to collection names?

Anyways, by this approach, we will be able to adjust collection names in the future as well, if we ever desire to do so, and anyone upgrading from a really old Pulp to a newer one will still be able to apply all the migrations.