Seems that last one wasn’t the final test. I found one more possibility, which I’m trying with this post. Hopefully this time it works and the truncated post is what the RSS readers pick up, while those who subscribe by e-mail get the entire post. I’ve subscribed by e-mail and through my RSS reader so will know immediately whether it’s working or not.
If not, then I’m going back to square one but will be a bit more vigilant about looking for sites like the one I found on the weekend.