I have run a course in writing skills for a professional services organisation. Interestingly (to me any way :-), I did this by audio-conference. When I ran it, I did it as 2 4-hour sessions, a week apart with an exercise to prepare and be critiqued by other participants in between.
I'd be happy to talk to you about what it covered. If anyone else is interested then I could see about running it as a proper course again.
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