This was from the early 2000's when I had first joined. It was from a guy at the time who worked for XOM. I believe he used to be on Noria if anyone remembers that site.
To this day it's been one of the best explanations I've heard:
"If an oil doesn't meet its specs, this means that blending quality is horrible." Or maybe not, there are many more places along the path for things to go astray than the blend kettle.
Compounder-blenders are likely to have a very generic formulation that is 2-3 generations behind the majors, their exhorbitant claims notwithstanding. I've seen tearaparts of some pretty high-profile compounder-blender synthetics that were just sad. These guys are buying an adpak from Lubrizol or Infineum and blending it with basestock, usually from ExxonMobil, since that's the company with the most spare basestock capacity. Many of their "specs" beyond the physical properties are read across from the adpak & the basestock specs. In other words, they've never run many of the tests they quote on their actual completed blends, or even on a lab blend. I've seen plenty of oils represented as "GF-4" whose names are suspiciously absent from the ILSAC web page. Blend quality in this market segment is likely to be all over the map.
The majors are typically going to give you a state-of-the-art formulation. Even if LZ or INF produces their adpak, it's likely to be a custom job developed in concert between the two companies and frequently sold exclusively to the major in question. (Once they develop the next generation, you'll frequently find these now-out-of-fashion adpaks in the compounder-blenders' products.) Their problems may be in the blend kettle, but the gremlins are much more likely to creep into their heavily distributor-dependent supply chains."
That's just based on tearaparts I've seen, from a group of some very talented chemists playing with some very fancy toys. "Synthetic" can be about as useful a term with oil as "organic" is with food. Plastic-related materials (as in high levels of VI improver, PIB & diester) are synthetic, but there are better things to put in your lubricants these days. (But those better components, specifically high-vis PAOs and non-ester cosolvents, cut into the bottom line, you know.)
Any supplier touting one specific additive might very well be using that as sleight of hand to distract you from thinking about the rest of a fairly pedestrian formulation.
The same goes for touting one property. "We have 8 ZILLION times better wear protection than Brand X (and those deposits all over the place, uh, they give you extra rust protection, yeah, that's the ticket.)"
Think of a lube formulation as a partly filled balloon. If you squeeze it one place, it's going to bulge out somewhere else. You can also think of an additive like a drug, it's got beneficial properties and side effects. If you push too hard on one property, it's going to hurt you somewhere else. Better suppliers will try to give you a comprehensive formulation that gives the best possible overall performance the current technology can provide."
