Okay, I'm going to quit trying to read anyone's mind and criticize anyone. Fact is, there was a cyclist taking up a full lane, bombing a hill, and someone got pissed. Remember folks. The roads only work because everyone wants them to work. It's just paint and a rule book and a bunch of people who don't want to collide with each other that keeps our roads working the way they do. Traffic accidents are unbelievable low considering the sheer volume of drivers and the sheer paucity of measures keeping them from colliding with each other.
Sometimes as cyclists, we have to do things to control others around us and use their unwillingness to hit us to our advantage. It's a thin line. Don't piss people off unless there is an immediate need for it. The only reason we can "take a lane" and hold cars back is because the drivers around us are unwilling to hit us. Never forget that. When we take a lane, it's an emotional appeal from us to the drivers around us to give us space. We are communicating that we need the space and, many time, we are not only communicating, we are forcing their hand. We are saying: "I'm going to be here and it's your choice to hit me or not, but please don't hit me". That communication, just like any other communication, can be in kindness or it can be rude. Too much rudeness and the social contract that allows us to get along on the roads breaks down.
People who are into "vehicular cycling" or other types of cycling advocacy have this view that the road is held together with laws and enforcement. This is blatantly untrue. Most the people on the road only know half the formal laws of the road. Half the cops don't even know the full lawbook. And enforcement? I go hundreds of miles driving between cop sightings. There is essentially no active enforcement of the laws of the road, and even when there is, it is not so much laws which are enforced, but peoples' behaviors. The road is held together by a social contract. It's people doing what they were taught when they were teenagers and looking to stay out of trouble and not hit things with their cars. With that comes a lot of unspoken rules. As cyclists, but also even as drivers, you are far better off learning and adhering to the social contract and the unspoken rules of the masses than going cross-current and carrying around a lawbook.
Anyway, enough of this. This is not A&S. I'll relinquish the soapbox.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter