If you take a sliding drop weight the weight is placed on a bar at various marks. The difference between 60 lbs and 59 or 60 lbs is probably 1 mm. Are you trying to tell me you can hit that 60 lb mark time after time with < +/- 0.1 mm accuracy every time? If you are I don't believe it.
Could it be that you mean the scale of a crank?
Dropweights have a bar of 40 to 50 cm for a scale from 10 to to 35 kg, meaning 16 to 20 mm per kg.
The dropweight I used and still have has a distance of 23 mm between kg's, so 2,3 mm for every 0,1 kg.
so I think that you can adjust this very accurately, because the scale is much wider than on a crank.