I saw the same account name + password, but don´t know the source either. A cool use of this account is, that you can PvP (friend) against your real account. This is a possible use of a second own account, I didn´t think of - Testing decks against special strategies.
Imagine several players would login there and begin a PvP (friend) game. What would happen ? Could only one of these persons play such a game simultaneously ?