As a past Local IAM Chief Observer I can appreciate her comment. Most people stop barely one car length from the parked car awaiting clearance of the oncoming traffic. Long distance vision is compromised as is the amount of steering needed to swing out. Hold back at least four car lengths and you will be amazed what a difference it makes to your long distance view.
Think about your towing mirrors compared to the cars standard ones. Your field of vision is much greater .
For decades I have said if everyone learnt to the IAM standard the roads would be a much safer place!
You seem to have misunderstood Dusty. Her comments were nothing to do with how far back I was, but my position in the road in relation to the kerbs. Her vision was obviously blocked as she was in the passenger seat. I could see clearly, and I had no need to swing out, there was plenty of room to manoeuvre with minimal steering input.
But otherwise, I take your point, but I always stop well back, particularly when towing.
John