all I know is that there is combine speed and football speed and I was shocked in the Superbowl when Fitz turned on the jets and took it to the house beating the angles on all the Steeler defenders. In Boldin's case it does not matter if your not fast enough to out run the first defender, you just knock him down. Forty speed for Dockett? does not really matter to me since it is not a forty yard dash to get to the QB