This is nice patch and I think this could be in F23. IMHO many people aren't using UEFI still so if they want to delete all partition of selected system and we skip one system it's not so painful. For master I should be more transparent solution where user will see what he/she doing though.
I'm going to PTO from Monday and return next week 12th Oct. I trust in your decision guys so if you want to fix this with your or @dwlehman patch you can push it or you can wait on me.