EDIT:Sorry to hi-jack,

DD and Mainline are great equipment, with a lot more accuracy than most can imagine. Except for the correction factor part mentioned which can be abused by the operator and tyre pressures that Rossco mentioned.

My 2010 Dynapack 5000 does not allow for operator correction factors (EDIT:this is done automatically via Dynapack's software) due to Dynapack's current approach.

The torque mentioned in the pic was uncorrected torque that the DD read. The operator did not choose the right torque parameter for the screen readout, which can be changed with the click of a button -- nothing to do with the inaccuracies of the dyno in this case, except operator error.