I will be interested in your taste and bake tests to see how Swiss cheese performs in relation to mozzarella and cheddar cheeses in how Swiss does or does not oil off.
I ran a few tests using the low-moisture part-skim mozzarella cheese, the mild cheddar cheese (it was orange from the annatto coloring), and Swiss cheese. All three cheeses are the Crystal Farms brand and have the fat profiles as previously mentioned.
For the first test, I shredded maybe a couple of grams of each of the three cheeses just to sample them raw and compare their flavors. The three cheeses had distinctive flavors, with the mozzarella cheese being the mildest tasting, followed by the Swiss cheese, and, lastly, the cheddar cheese, which had the strongest flavor. I also made a blend of the three cheeses, with about 4 grams of each, and tasted that blend raw. That blend had a distinctive flavor profile that was unlike any of the individual cheeses but the cheese that stood out the most was the cheddar cheese. For comparison purposes, I made a similar blend and baked it in a pie tin in my countertop toaster oven at around 350 degrees F until the blend melted, about 4 minutes. I then tasted that cooked blend. Again, the blend had its own unique flavor profile but it was clear that the cheddar cheese and the Swiss cheese dominated the flavor. However, I can't really say that I could detect the Swiss cheese as such, only that there was a flavor in the blend that was different and stronger than the flavor of the mozzarella cheese. I don't think that I would have been able to pick out the Swiss cheese in a blind test, at least at the level of that cheese in the blend I made.
As the above bake test was being conducted, I also looked for the degree of oiling off of the cheese blend. There was clearly some oiling off, with some fat on the top surface of the cheese blend and also under the cheese blend, but, at the amounts of cheeses used in the blend, the oiling off was not all that much. To get a better sense of the oiling off propensity of each cheese, I conducted another test. For that test, I shredded about 7 grams of each of the three cheeses and formed them into small mounds that were placed in my pie tin with a fair amount of spacing between the mounds. I baked the three cheeses and then observed the oiling off of the three cheeses. The mozzarella cheese had the least oiling off, followed by the Swiss cheese and, lastly, the cheddar cheese (the oil had an orange tint), which had the most oiling off. These results would seem to suggest that high fat cheeses have a greater tendency to oil off than cheeses with lower amounts of fat. However, there are other factors that might be implicated. For example, the three cheeses also contain different amounts of moisture. There was no way for me to calculate the water content of the three cheeses that I used, because the Nutrition Facts do not specify those numbers, but the generic numbers for the water content is different for the three cheeses. For example, a generic low-moisture part-skim mozzarella cheese contains about 46% water, generic cheddar cheese contains about 37% water, and Swiss cheese likewise contains about 37% water. Even if water content is a factor in the way that cheeses oil off, the fact remains that the cheeses with the highest fat contents appear to oil off the most.
I think the best and truest test would be to make a pizza with a blend of the three cheeses. Maybe a blend with equal amounts of the three cheeses, or maybe with an overweighting of the Swiss cheese, would be a good place to start, mainly to see which flavors dominate and also to see if the Swiss cheese can be detected in the baked pizza. If it can't, especially in a blind test, then one would have to question whether Mack's would be using such a cheese in a blend for its pizzas. Of course, this is a logical conclusion that might not hold up in the real world in the case of Mack's.