Hi
I also find it interesting to see the following app note:
http://www.stabilant.com/appnt32h.htm
I have never seen the problem they are talking about and
I have a sea going sail boat. According to their note,
this should be the worst condition. Makes me wonder
what I might be doing that is different than what
they are doing?
Are you cleaning periodically with the silicone? Perhaps
you're cleaning it often enough to prevent the silicate
from forming...
-dq