To me, CW has only one advantage, it permits a broader group of users the necessary privileges to edit something.
I use it when answering a question that might not suggest the same answer a year from now, or even a few months from now.
As far as I know (ICBW), the only way to remove down votes is to delete the answer and recalculate reputation, just like up votes go away when an answer is deleted and reputation is recalculated.
I don't see anything terribly wrong with people wanting to stop the onslaught of down votes while they fix their answer, but the best way to do this is just delete it, edit it, then undelete it.
To me, converting an answer with lots of down votes to CW is like saying "Ok, you don't like this answer? you fix it!". So, perhaps the best thing to do is just fix it if you can.