There has been a problem in the rating of Round Robin Rapid events with FIDE. A bug/programming error, which does not appear in Blitz events, has been computing the Rc (average tournament rating) using ZERO (0) for unrated players. It happened more than once so it was not an anomaly. The problem is with the initialization of FIDE ratings for unrated players in Rapid
In one of my events with ratings of 2024 (x2), 1989 (x2) 1823 (x2) and unrated the Rc was computed as 1459 and the only way for that to happen is to average in 0 (x2). One unrated player played in two RR Rapid events, scored 6.5-2.5 against 1943 average and .5-3.5 against 2 unrated, so 7-6 and had now has a rating of 1355!
I spoke with Jeff Solas with chessmetrics.com who confirmed the problem and he has contacted the QC Secretary, the Ratings Office and the FIDE programmer in the attempt to fix the bug.
So, until it gets fixed, probably not a great idea to have FIDE unrated players in your Rapid RR. No problem with USCF rated Quick RR though.
Michael Atkins