This is a good discovery,blu - it's one the PES fans methods (I will shamelessly gloat and state that I am the original founder "Sepakbola" from SG,
"Does Anyone Else Do This" in the PES4 days) used for the PC version of WE/PES.
I too wish there was a way we could actually go in and edit globally - it would be a beautiful thing, with the touch of a button - all attributes edited. Oh well.
I have been meaning to do this - but the absolutely slow transition frames between the menu and edit player are very frustrating to go through.