Reading it back, I did sound overly aggressive to the poster. I didn't mean that.
The attitude I was talking about is, "I don't see how it's safe because drivers can't get past".
The way I see it, the only ones in the wrong in that situation are the impatient drivers who are breaking the law by trying to pass when it is not legal or safe.
The main reason cycling isn't safe is because drivers are overtaking unsafely when they might be delayed by a cyclist.
People seem to think that it's acceptable for drivers to break road laws just because they are being inconvenienced.
This behaviour is not acceptable, and indeed is illegal (although unfortunately not enforced - thanks for protecting our safety NSWPolice!).
The post I was replying to made no mention of the fact that drivers are meant to exhibit some semblance of patience from time to time, and seemed to be saying that cyclists are unsafe on the road because they can't maintain a 70kph speed, when in reality cyclists are unsafe because drivers are breaking the law.