AHA! Now there is the rub, from my point of view. Just a thought here.......

But, in your attempt to "teach" the new Dom, wouldn't a novice sub be more ideal? That way, as she were performing, and a glitch arose, you would then be able to better teach the Dom on how to handle the practical problems that always seem to arise...ie: training/ conditioning the sub to respond in the manner YOU prescribe.

After all, having any D/s relationship, takes much work on both parts, to self train/condition and train/assist the other into their respective role.
A wonderful point Katmandu, but I like to use an experienced submissive to teach whatever it is I'm teaching so that the new dominant can see or experience how it is supposed to go. While demonstrating I put in the appropriate cautions. Like - If you leave these clamps on too long, this can happen or - she might react badly to x, so try y if that happens- and of course the all inclusive- Everyone is different so go slow your first time. Using a novice would be more realistic for the new dom, but it also could be emotionally or physically damaging to a novice submissive who may not want to safeword for pride's sake. The closest I come to using a novice is when I have trained in couples - myself and my submissive with a newbie couple- but even there I try to keep it simple and easy so I and the new dom don't overwhelm the novice submissive.

Thanks for the great responses folks. Keep 'em coming.