The thing with Weidman is that he's still just a brown belt with no BJJ credentials to his name whatsoever outside of that extremely overrated performance against Galvao.
Yes he has no BJJ credentials aside from beating that one Brazilian world champion, and of-course beating that other Brazilian world champion on 10 days notice with a 30lb weight cut wouldn't impress you much. I mean Galvao and Maia are nothing compared to Leites and Lutter.
You could also point to his D'arce choke victory over Tom Lawlor and his standing guillotine chokes as being mere lucky breaks and not indicative of any "real" submission skills.
But I mean what's more important his accomplishments or his belt.