Someone is working on some notes for the Macarthur Blvd "Share the road" meeting for me, but in the meantime, WUSA was there and has some footage. They reported it as "heated".
The disagreement between the two essentially boils down to this: drivers say bike riders take up too much of the road on Macarthur Boulevard, while bike riders say drivers often drive too fast and are too close to them when passing.
One is an annoyance and the other is dangerous. That's not to say that one should be annoying if they can avoid it, but there really isn't room to move over safely in many cases, and moving into single file is not going to help.
They followed this with a "Let's Be Real" segment on the Macarthur Blvd with Derek McGinty. I'm mostly with him (except for the part about "not taking up a lane of traffic") right up to the part where he advises drivers to lightly honk when they come up behind a large group of cyclists. That is not going to help.