A WordPress build i'm focusing on really wants to pull in tales from nourishes, after which allow customers from the site to include comments and star rankings to them. It does not really appear such as the correct useage of rss in my experience, but is kind of factor possible without posting/syncing the nourishes using the database?

At the minimum you'll need a way of associating rankings having a particular story. What this means is storing some unique 'story' identifier so that you can retrieve it later and calculate its rankings and comments. You can get away without syncing the whole feed should you could develop a trusted way of determining and associating the initial_id I pointed out.

Example:

#dbo.stories_comments
--------------------
|story_id | comment|
--------------------
| 12345   | Lorem..|
| abcde   | Ipsum..|
--------------------

Like I stated, the tricky part is approaching using the story_id

Most probably you wouldn't want tales customers have chosen onto disappear once they fall from the Feed, so you are going to need to store a duplicate of stated story inside your database.

Therefore the short response to your real question is "No."

Furthermore, I do not use whatever reason this is not a "correct useage of rss".