Just saw this thread. Not much to add except that in the pic you posted Boofer, the mechanical advantage is around 16 for the lever on the left. The four foot lever divided by about .5 feet (the distance to the follower) is 8 then the pulley doubles that. If the weights they add are 2.5 lbs, then the weight on the top cheese is 40 lbs and the bottom cheeses have 20 lbs each plus the weight of the top cheese which is probably another 20 lbs making them all the same. If the hoops are 8 inch hoops that comes to 50 square inches or a psi of 1.2 on the top one and .4 psi on the bottom. I would guess that the max amount of pressure applied to these cheeses is 4 times that (about 5 psi) since there are about 4 weights available for each press in the picture. They are also pressing in whey, so does that mean this is probably gouda or something similar? 5 psi is about right for gouda, right?
As far as your original question, If you look at a lot of the older presses, they all are very tall to allow for several stacked cheeses. They usually did like this the lady in this pic and distributed the bottom layer with more than one cheese to compensate for the additional weight of the cheeses on top.
My whole point is that people were smart enough to figure that the additional weight on the bottom cheese had to be dealt with and they did it by either constantly switching them or having multiple cheeses on the bottom layer.