The Sempre should in no way damage your 5970 providing it is set up correctly. Each watch is different so pointless comparing numbers on the Sempre meter. My strategy was to adjust the Sempre to a low torque setting and observe as it is wound. Usually it stops before the watch is fully wound (check by taking it off and manually winding)so I keep increasing the increments until I get the 5970 to its max. The unwinding merely takes pressure off the crown.
If it is of any help my torque runs at between 30 -40%