Joe, this bread was done by hand as demonstrated in the pictures with the recipe. On the other hand, the challahs I posted the other day were made with a 20 qt. Hobart. The challah recipe has a lower hydration, and would be all over the place if I tried to mix it by hand. I'd guess that 15# is about the max that would fit in one of my plastic bins (I keep 4 on hand). Obviously, your oven capacity would be your limiting factor. Before the WFO, I'd have 3 separate ovens going to do my once a year 50 loaf bake-off, usually with 8 loaf batches.
GG, I use a commercial scale that reports in hundredths of a pound, not ounces, sorry.