I believe you've got the wrong Dave, as it wasn't me who posted the Optimist message.
-Dave Muhlert
proud to not be involved with Optimist sailing in any way 
http://sailfast.netfirms.com
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Message: 1
Date: Mon, 5 Aug 2002 13:06:00 +0200
From: "Rob Walker" <rswalker@mweb.co.za>
Subject: Calculating Optimist Skipper ratingsTo Dave Muhlert (Sailwave)
Hi Dave, did you get the Optimist skipper handicap formula sorted out?
I'm still battling as our old system we had
c=e-(r/6000*e)
This gave each skipper a handicap based on 1 hr (6000secs) of racing and
their handicap (rating) looked something like 475 for the better
skippers and 1128 for the worst. I used a new rating for each race based
4/5ths old rating + 1/5th new to iron out any extreme fluctuations due
to a spurious/chance result.Please could you detail your system as I'm not 100% with ours,
especially the formulae. How have you determined a rating and are any
Optimist series using a wind rating?Thanks,
Rob Walker (Optimist Coach, Henley Midmar Yacht Club, South Africa)