Stuart. For your own sanity, stay calm. Jackson - Kent spent 10 years analysing the string numbers on W3 coin harps only to conclude at the end of it that there was no significance.
Personally, it makes more sense for the stops to be personal privy marks as an engraver id, as there are a number of types used, but thick string or thin string in varying quantities is never going to fly given die degradation. Stops however, are rarely confused.