The default Atom feed that ships with Movable Type is a full feed. It publishes your entire blog entry, not just the Main Entry Body or an excerpt. Although many people prefer full feeds, sometimes using a partial feed (publishing just part of the entry in the feed) is appropriate. For example, if your blog is commercial and your business model depends on getting readers to your site where they can view ads, then you might want to publish a partial feed, giving feed readers enough content to be interested to click through to your site. Also, if you publish a partial feed, feed aggregators and content slurpers will be less able to lift your content in its entirety. A key benefit to including a "Continue Reading 'Name of Entry'" link in your partial feed, is that when feed aggregators pick up and republish your content, it will include a link with SEO-friendly anchor text back to your site.
To turn your full Atom feed into a partial feed, all you have to do is remove one line of code from the feed template. Towards the bottom of the template where it says:
<content type="html" xml:lang="<$MTBlogLanguage ietf="1"$>" xml:base="<$MTBlogURL encode_xml="1"$>">
<$MTEntryBody encode_xml="1" convert_breaks="0"$>
<$MTEntryMore encode_xml="1" convert_breaks="0"$>
</content>
Remove this line:
<$MTEntryMore encode_xml="1" convert_breaks="0"$>
and save and publish your template. This will produce a partial feed, with the Entry Body as the part of the content that gets published to your feed.
The next step is to add a "Continue reading NAME OF ENTRY" link, so that in your readers' feed reader program they can see that there is more content if they click through.