User blog comment:EDN1980/Mark, God and the Darkness./@comment-95.112.133.60-20150912190412

Depends, if God weared the mark for, let's say 2 hours before giving it to lucifer, I would not have such a great impact on him. I think it is safe to assume that a more powerful being is more resistant to it's effects. Anyway, we know that Lucifer still was "evil" after he gave the mark to Cain, so the effect was not reversible, so Dean should still be angry even without the mark, but I guess they wont make it that way, he is one of the main characters at all.

I think Amara will enjoy to tell Dean, how easily she/ it influenced him to be a killer through the Mark