Here's a followup:
I phoned Canon in Toronto December 23rd. Although my 40D was thirteen months old, the guy on the phone told me to get it to them quickly and they would service it under warranty. I shipped it Christmas Eve, at my expense (about $50 insured). I was pleased to get it shipped back (at their expense) January 5th. That's 11 days, but includes Christmas, Boxing Day, New Years Day, and two Saturdays and two Sundays, so actually only 4 business days. Very impressive.
The included report says the focus was adjusted, and when i tried my Sigma 30 f/1.4, it focused much more accurately than it had previously, although not quite as well as when used on my 50D where I have micro-adjusted it. I now believe any further improvement will need to be done by Sigma. However, the focusing on the 40D is now so close (at six feet it is pretty much exact when stopped down to f/2) I will now probably leave it as it is.
The camera had also been cleaned. Great!!
As Canon promised, there was no charge for any of this work.
So, my opinion of Canon Service in Ontario is most positive. Thanks, Canon!
Maxdave
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