With due respect, Pablo, you're going to have to get out of the Amsoil house more often. The prices I'm quoting are not "rare" and are, in fact, very easily discovered if you look around. If I am willing to concede an Amsoil preferred discount to those that would seek it, then by fairness you should concede HDEO is easily attained for $2/quart. I'll give examples:
Delvac 1300 CJ-4 is around $10/gallon retail in the midwest, and $9 is not unheard of when on sale. O'Reilley Auto parts was just last week selling it BOGOF for $12.99, which makes it a whopping $6.50/gallon ($1.62/qrt)! (see this BITOG thread from CO:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1619476&page=1) My local Menards sells Rotella CJ-4 each fall for $8.99/gallon, in both 15w-40 and 10w-30. The local AAP just recently had Tection Extra, 3 gallons for $27 ($9/gallon). The examples go on and on. If you can't find dino HDEO for around $2/quart, you're not trying hard enough. Like it or not, Amsoil is (as a generalization) about 4x the cost for HDEO, comparing the preferred customer price to easily attained store sales.
If you extend the OCI out 4x or greater with Amsoil, then certainly Amsoil fluids are plausible and make sense, and will perform in a stellar fassion. While I have never used Amsoil, I do not subscribe to the "Amsoil conspiracy" mentality. I have used PAO-based products, with great success and been very pleased with them. However, unlike some, I actually analyze my "needs" and seperate them from my "wants", then balance the pros/cons of both, and make an informed decision. But if one is constrained by warranty (or mentally) to short OCIs, they surely won't get 4x less wear by using a high-end PAO (regardless of brand) over a quality dino HDEO. I would challenge anyone to show me convincing evidence of successive UOAs showing 4x less wear for any brand PAO, compared to dino HDEOs, for short-to-moderate OCIs. Therefore, this is where I have a problem with your blanket statement of Hypuron not being "better" than Amsoil. Depening upon OCI interval, the Castol product might certainly be "better" on a "value" basis, and still give excellent UOA results.
To the other topic, I agree with you. Oxidation cannot be understood unless the baseline is known, and the type of testing used. Your suggestion of contacting the lab for clarification is spot on.