There's no way I'd take McNabb as our QB over Batch or Dixon. McNabb has been washed up for the last 2 years and wouldn't the foggiest idea of running an offense like the Steelers do. As fragile is Batch is atleast he knows the offense. Same with Dixon.
I think it was just a matter of not being prepared on his part. I know we all remember what he was able to do last year. I think this is another reason why you let Batch start on MNF if the Ravens beat the Chargers. Give Batch some reps and let Ben get some much needed rest.