In reply to 3 Names:
Not offhand, and I suspect it could only become an issue on a multipitch stance if you also had part of the belay clipped back into the rope loop. Still, however small, it's an avoidable risk with no great or obvious benefit compared to using one's harness as it's intended to be used.
I sometimes clip one of the rope loops as well as the belay loop when I'm belaying on multipitch - because why not? little bit of extra redundancy - but I see no sensible reason to avoid using the belay loop altogether.