Offering multiple feeds for the same entries is perfectly fine.
This is commonly done to provide different formats, or, like in your case, to offer a feed with the full content and a feed with excerpts only. Another reason might be to offer feeds with different entry count (e.g., the newest 10 items, and the newest 50 items).
Full content or excerpt?
That said, I don’t agree that a feed with the full content "isn't normal practice", and I don’t agree that only an excerpt feed "meets standard criteria".
It’s typically more useful to provide the full content:
- feed reader users can read your content within their feed reader (without having to visit your site in their browser), and
- they can use filters (and the search function) in their feed readers that work with the full text.
In case of Atom, you could even provide both in the same feed: a
content element for the full content, and a
summary element for the excerpt. (I guess other feed formats allows this, too.) Sophisticated feed readers might offer the user the choice what to display.
Reasons for providing only the excerpt (typically not in the user’s interest) include:
- the author wants the users to visit the website (e.g., because of advertisements)
- the author is afraid that a full-content feed makes it easier for scrapers to "steal" the content
If providing multiple feeds, make sure