@ WEBSTER: Not a problem, glad to be able to contribute. You're right, this is very useful information. Somehow, I've been running around all this time thinking that 11 knots was the best - wrong, wrong, wrong

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Hmm, methinks this is what I get for ignoring the golden rule: "Never Volunteer", ha, ha. However, since I did it to myself, I might as well finish the job. I'll run the scenario with a balao at the speeds you requested, and post it up this afternoon.