The more I think about this fix, the more I think there are options to go wrong on upgrade. I have seen this personally.
My feeling is that we should keep this as simple as possible. Install MySQL 5.6 on new installation but not change anything on upgrade.
Then if someone has a working system and they choose to not upgrade MySQL, then can carry on as before. However, if they want to upgrade MySQL they can do a complete clean install.
Sure, a complete install is a pain, but far less then if an upgrade goes wrong and you then have to do it anyway.
My feeling is that we should keep this as simple as possible. Install MySQL 5.6 on new installation but not change anything on upgrade.
Then if someone has a working system and they choose to not upgrade MySQL, then can carry on as before. However, if they want to upgrade MySQL they can do a complete clean install.
Sure, a complete install is a pain, but far less then if an upgrade goes wrong and you then have to do it anyway.