What is relevant is if they have the skills to teach, and if they are a patient rider. IF they can be smart, nail body position and line, and work with the slower riders in your B or Novice group, SURE!
However, if they can't be SAFE, and judge those around them well, and ride well while looking behind them, don't use them.
Remember Carol Drucker? We have had a few CRs over the years that were absolutely EXCELLENT with B group riders, yet they did not have the pace to run A group themselves.
Just my .02.
Carol "Mom" Drucker - she taught me a lot starting out, and gave me shit about not just turning the bike when I went to check the gravel in T-12 at Road America. I miss her being around.
I'm slower than most of the A-group out there, but no-one has bitched about getting around me. I do know that I'm faster than some CR's in other orgs, but that doesn't mean they can't help teach the novice/beginner riders. Maybe they only CR in B-group, then as the people progress due to their instruction, the faster CR's can take it from there. If they have excellent body position, and consistent lines, then they are teaching by example, and not just how fast they can go.
If the ORG trusts them, then I'll trust them, but I knew enough to ride my own ride when I was learning. It took me longer to get to A, but the end result is the same.
The only person I might be leary of is Ron Hix, because he tends to run at his AMA pace as he turns around wondering why my 12 year old bike won't keep up.