Bill and Brion,
Thank you for your replies. I do not know if a line drawing of the rigging would help. This drawing is for a Force 50 with wooden masts but our vessel is rigged the same way.
The primary reason that I have been given for the springstay being insulated is lightning protection. The helm is located directly behind the mizzen and if lightning strikes the main it would not be transferred to the mizzen and this would protect the helmsman~?
Lightning is one of those controversial subjects and everyone has a different opinion. We use out insulated stay as our SSB antenna and it works quite nicely!
Thanks again,
Dan Pitman