I'm an avid cyclist and a motorist of many years. I've seen some hair raising close calls on my bike, and a few in the car too. I believe we all should be more tolerant of each other. There are lots of pros and cons to each argument, but the bottom line is, cyclists are legally entitled to use the road, and the cycle path. Using the cycle path is my preference but it is quite often not possible, due to dog walkers (with dogs off leads), and groups of pensioners who think they are more entitled than I. But that said, where I can, I use the cycle path.
I would never dream of riding two abreast, especially on narrow roads. It's just plain rude, even if it is legal. I think a lot of people need to use their common sense, and many motorists (and cyclists for that matter) are in too much of a rush to use their brain accordingly.