Presumably he deleted the FoV saves with the new character (started in the add-on) before creating/continuing with a character started at the beginning. There is a stupid 20 save limit on the Xbox, and while it is possible to backup saves to a USB flash drive, it is kind of a pain to manage sets of saves that way.
Well actually, I have two memory cards and an internal memory unit on top of my HDD. But alas, I deleted my character's saves before I realized those skills weren't available on an ED character.
EDIT: Nevermind, I kept a couple endgame saves from my FoV character.
EDIT 2: Or not. I can only train Dual-Wielding to 15. The others seem stuck at 13.
