8 1/2 Lbs enormous? hummm . That is nutty. My Suzi is around 7-8 lbs I think, and she is small , IMO. I also have a 2LB Shi Tzu puppy and she is tiny. There is a big difference in size, however one is only 9weeks old. That is to be expected! I would not ever comment on the same breed of dog being too small or too big > What is important is the health of the animal. Who cares what size the dog is.
That lady must of been one of those people that did concern herself with "size does matter" even if it is a Lb and a 1/2 size difference, there is more to love ! that is what I would of told her