I think it's stretching things a bit by invoking physicists unless it's meant that without a physicist we wouldn't have the transistor that made modern computers possible which in turn made CNC machinery possible. But a good machinist with the proper equipment can make an engine at least as good as a CNC machine. Just not as fast. But that good machinist relies on someone with a modicum of engineering to design the engine. A lot of trial and error has led to the slow development of modern engines as we know them and in some cases this development has been an off shoot of racing, the same as happens with cars. A perfect example is ABC technology which came about because of a problem with cast iron pistons in 2.5cc (.15 for the Yanks ) in control line speed. Say "thank you Super Tigre" .

As for engine temps and cooling, which is what this topic is supposed to be about, there's so much variation with the amount of cooling designed into different engines it's near impossible to say what's enough. Probably the worst cooled engine (going by fin area) is the Fox 35 (yes, I know it's designed to run in a 4 stroke most of the time) while among the best would have to be Super Tigre. Come to think of it the Dooling 29 is probably even worse than the Fox with a couple of fins around the cylinder and none at all on the head. And no one can say that was a badly designed engine!

But no engineer would design cooling fins as we have on our engines. The best cooling fins should be triangular in shape to give the greatest mass and easiest heat path closest to the liner then taper down as more heat gets extracted over them. The machinists said too hard/costly so we have straight machined fins. They work well enough.