So why doesn’t he just say that drivers shouldn’t be overtaking cyclists there, rather than suggesting it’s unreasonable for cars to be held up behind them? Meanwhile you’re only talking about a handful of streets in a very small area there – outside that, but still within Cambridge City there are plenty of roads which are wider (the same width as roads anywhere else) and where traffic flows more freely, but which are also used by cyclists, where Operation Close Pass would be wholly appropriate (I also have plenty of experience of cycling and driving around Cambridge).
In any context the statement there is ridiculous, because he’s basically saying that if there isn’t space drivers should just overtake anyway. But it simply doesn’t hold up in the context of Cambridge, where most vehicle movements take place outside the narrow roads in the centre.