My first reaction to your questions was that perhaps your dough batch size was too large for your KitchenAid stand mixer and that possibly that was responsible for the results you got when using the KASL. However, when I checked the operator's manual for my basic KitchenAid stand mixer, the only admonition was to keep the amount of flour (stated as all-purpose flour) for yeasted doughs below 8 cups. Allowing for modest hydration levels and the addition of other pizza ingredients, I estimated that my KitchenAid stand mixer can handle about 3.7 pounds of dough. In your case, at 1413 grams, the dough batch weight is a little over 3 pounds. So, it looks like you were within the recommended limit of your machine, if it is anything like mine.
The second possibility that occurred to me is that your two flours have different moisture contents. Generally speaking, at the millers where the two flours originate, the moisture content of the two flours should be the same because of the way that the millers adjust the moisture content to be within the limits required by law. However, the flours may get to your pantry via different routes and with different transit times and be subjected to different storage and environmental conditions along the way, including variations even within your own home. These changes can affect the performance of the flours. Moreover, room humidity at different times of year can also be a factor although it will not be as great as many people believe. At the moment, with the colder weather and home heating systems doing their job to warm up our kitchens, moisture will be removed from the air, making the dough seem likes it needs more hydration. Whether that was a factor with your KASL is hard to say. You may have to do some more experimenting with the KASL to see if your room humidity was a material factor in the results you got, or it was only a flour moisture content issue.
For some interesting information on rated absorption values for some of the King Arthur flours, you may want to take a look at this thread:http://www.pizzamaking.com/forum/index.php/topic,4646.msg39204.html#msg39204
. You might also want to read the items linked in that thread. Unfortunately, a couple of those links are no longer active, but I think you will get the general drift of things.
With respect to your question about whether there is some sort of correlation between the absorption characteristics of flours and baking temperatures that makes one flour more suitable than another at lower baking temperatures, I can't say that I have read anything of that nature. However, all else being equal, including bake temperature, skin thickness, etc., a high hydration dough should retain moisture longer than a lower hydration dough. But, in practice, dough formulations can vary quite widely and may include ingredients like sugar and oil that also work to retain moisture in the dough during baking. In such a situation, hydration is just another aspect that has to be taken into account with all of the other aspects.
I am not sure which result you are referring to in your last question, but in general I would say that if a flour is hydrated more than its rated absorption value, it will be more fragile in the sense that the dough is likely to be more extensible and harder to handle, especially if the differences between the rated absorption value and operational hydration value are large. Under those types of conditions, the doughs should be able to retain moisture longer during the bake. But, as noted above, it is not the only factor. You might also keep in mind that it is possible to use high oven temperatures and short bake times to help retain moisture in the dough. Usually the issues in such cases is whether you get the desired degree of crust coloration with the shorter bake times.