Based on the fact our road tends to have ample space to park at the weekend and in the evening, I'm confident several of the cars parked along it during the day belong to commuters.

I do agree, CPZs can be a pain if parking for non-permit holders is banned all day long. But putting restrictions in place for a couple of hours around lunchtime might be a good compromise. If nothing else, it'd prevent people from leaving their cars there all day long.