First of all David Carr was sacked so many times in large part because he took a lot of sacks. He took a lot of sacks because he wasnt very good.
Most people noticed that when the Texans switched QBs the number of sacks they allowed went down a great deal. Also, when Carr played elsewhere, that teams number of sacks allowed increased significantly.
Finally, this whole idea that somehow David Carr's career was derailed by his OL and it was all because he was rattled and his confidence was shot is complete and utter nonsense. Carr's career wasnt any good because David Carr simply wasnt a good QB. He also took a ton of sacks because he had zero ability to escape pressure, was very slow making reads, and typically made errors when he did throw. He had a strong arm though. Just another overrated guy coming into the draft with a rocket arm. Thats all.