Interesting post. I would have missed this otherwise. That said, on the clips I watched there are actually two C300s (or equivalent, it's hard to tell) on the interviewer and interviewee. Locked off and constantly running so nothing is missed. The whole thing could be edited with just footage from just these two and the image is very classic, very clean. The cheaper cameras are only there, I suspect, to inject an element of spontaneity and dynamism, conveying an impression of intimacy and sincerity associated with (apparently) lower production values. It's very well done propaganda.