He did take responsibility.
It wasn't a mistake. It was a conscious decision that he made. Regardless of the decisions he's made off the field, his time with Washington was coming to an end anyway because of his decisions on the field. This dude has not come close to what he did at OSU in the NFL. He's simply another QB who lit it up in college an sucked in the pros... Rick Mirer, Ryan Leaf, Jamarcus Russell, Brady Quinn and others come to mind.