I've found that it's often very hard to judge if somebody has behaved "acceptably" in traffic from hearing a story told, precisely because there are so many small details that affect the situation. Like how fast were the bikes going, did they change position, were they aware of the situation, were they blocking cars, how long did this go on, what were the road conditions like. I could probably defend either viewpoint quite sensibly. So I try just to be aware and flexible in my riding, help traffic flow but still stay safe, and not think much about what others are doing.
Winter riding is much less about badassery and much more about bundle-uppery. - malkin
1995 Kona Cinder Cone commuterFrankenbike/Selle Italia SLR Lady Gel Flow
2008 white Nakamura Summit Custom mtb/Terry Falcon X
2000 Schwinn Fastback Comp road bike/Specialized Jett