Let me answer your question with another question.
If I were to trade you my Bitcoin for your litecoin, how would I be able to resolve a dispute if you had sent me your litecoin directly that I would not be able to do if I was acting as escrow for my alt?
What is the difference? In both cases there is the exact same potential bias
Thank you for proving my point. In a scenario where you secretly "self-escrow", you would have a bias similar to two parties trying to resolve a dispute in a trade without an escrow. As an escrow, hiding this bias from the other party is misleading and disingenuous.