I would suggest having it tested with a timer graph with the chronograph both running and not running.
There should not be a significant difference in gain or slow down time with the chronograph either on or off.
If it is properly oiled and has no extra friction from the hands gears etc, the timing can be adjusted by the timing screws.
Good luck…

: That is significantly better than i am achieving so thanks for the
: heads up, something must be amiss either in my process or the
: watch - i shall investigate further.