I am extremely pleased with myself for choosing a natural fiber. Even though I am working with wool, it is a light weave and it really does breathe. I sat next to my friends who had the fancy polyester robes and they were almost ready to pass out -- and this was an indoor ceremony. I was quite comfortable.
Once the robe is on, the weight of the back of the garment, combined with the weight of the hood pulls the garment back so very quickly the garment is supported by the front of your throat, and not the shoulders. I did not have time to had the hooks and loops and buttons the support the hood onto the gown, but I don't think that would have helped much.
I ended up pinning the hood to the front shoulder of the gown. Then I rant the loop that came off the front of the hood down the front of my dress and ran my front fastening bra through it. This works like a charm. I understand that men often attach the same loop to a shirt button, but women don't always have that option.
My mom and I have spent a considerable amount of time considering other counterweighting measures and harnesses that could be sewn inside the robe. There will be more posted on this subject to be sure.