CORS simple request diagram

Anne replied..
 > JeffH wrote..
 >> The spec's exposition of its functionality would be greatly enhanced by
 >> at least one diagram, e.g. a "ladder" or "swimlane" protocol flow
 >> diagram.
 >
 > If anyone can create one I am happy to include it.

Please see attached for example of the sort of diagram I was imagining.

=JeffH