So you are trying to understand if it was the surgery or the chemo that helped, is that it? I'm not quite clear on the problem. Do understand your wanting clear explanations and access to the data.

I think the idea is they use chemo to target any remaining (hiding) cancer cells after surgery.
Something is working, yes? You are winning the battle, at least for the moment. Maybe a deep breath and some gratitude?

Let me know if you are able to get the Herceptin and what insurance you have. I want to try it! I have to get rid of metastasis before I am eligible for surgery, if ever.