While reading news and mail in Gnus, I started to score authors in the Digest mails I subscribe to.
Looks like that is not working correctly, as I thought it should.
The entire digest in the Summay Buffer is highlighted instead of the articles from the specific person (which is what I score on).
Thinking this through, obviously the digest is a compendium of a number of mails with lots of headers stripped into 1 file, so the ticks seen by Gnus is on the entire digest I guess.
& you do have to hit C-d to see the articles individually anyway.
Oh well, so scoring on mail digests is not a good idea.