Papa Georgio said:
Any other episode Carol revealing that she killed Karen and David would have been the big moment but it almost came and went without much notice. I think Tyreese was/is just numb and enough time has passed since it happened that he has come to grips with it. I think his reaction was a bit under-played though.
I think the whole transformation of Carol is one of the best story lines by far. I wanted to slap her myself in the early shows for being so weak. I almost couldn't stand her. Has anyone else come close to such a change in either direction?
Under played, no. I think the point was he was living in the pre zombie world where there are things you don't do because Tyreese is a good guy, wouldn't attack the prison, saved the baby, tried to save his pals even when they went with the gov. Which is why Tyreese was so mad about the "wrong" of murdering Karen and the red shirt.He knew when he essentially sentenced Lizzie to death that this crazy mixed up world makes good people do bad things.
He could hardly condemn Carol for murdering Karen to save everyone after he just condoned murdering a child and then sending Carol out to do the dirty work.
He was forgiving himself by vindicating Carol.