On the matter of the hydration value to use, I was hoping to get the latest feedback from Bob for the remaining dough ball that he had prepared, or so I thought. However, I am beginning to think that the extent of fermentation may be as critical as the hydration since a long fermentation may cause a weakening of the gluten matrix and make the dough softer overall. There are ways of offsetting the weakening of the gluten matrix that come to mind such as using a lower hydration value, reducing the amount of IDY (but still above 2%), using ADY in dry form (above 2% and maybe as high as 2.5%), using a longer knead in order to more fully develop and strengthen the gluten, or shorten the fermentation window. I think the desired end result is a dough that can be formed into a skin with a fluted rim that will remain erect and where the flat part of the skin does not sink into the holes of the perforated disk or cutter pan. Working the dough while cold should also help and yet be able to withstand a 15-20 minute rest while on the disk or cutter pan.
With a pizza as shown in the photos with sausage, pepperoni and peppers, and especially at the larger size noted in the photos, and a 425-450 degrees F oven temperature, I think it is perhaps inevitable that there will be a gum line, especially in the middle part of the crust.
I found that clicking on the HRI photo at the webpage you referenced allowed me to view all of the other HRI photos.