What is the molecule size distribution of dino oil vs semi-synthetic oil vs full synthetic oil? Where does Castrol Syntec fall?

Note, this is not a question of what is better. I don't want to get into a dino vs synthetic debate since it has been done to death. But I have been doing a small amount of reading and have a question. As I understand it, oils fall into group categories based on the feedstock used and the subsequent processing. Dino is from crude oil + various hydrocracking and cleanup to remove impurities and products that can breakdown under lead and load to leave deposits and undesirable chemicals (like acids) behind. Additives help suspension of particles, stablize viscosity, etc. The resulting collection of molecules must be quite diverse in size and properties. Synthetics on the otherhand have a feedstock that is a single chemical or collection of pure chemicals produced from a synthesis of raw chemicals, not by the refining of existing crude. The distribution of molecule size must be significantly narrower. Castrol Syntec apparently hydrocracks to the extreme and gives a near-synthetic product in resistance to breakdown to undesirable deposits, etc. But I suspect it has a range of molecule size that is more comparable to dino oil than synthetic oil.

Is my understanding correct?

Bill
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