Well that's great to have the success criteria on record (so many times from one poster).
So if PU does not clean the soft build up under Artems valve cover, then the verdict from this group should be that Pennzoil are just as bad as Auto RX with their product claims that relate to cleaning.
Indeed, as a large multinational that have the resources to do extensive testing, in some ways it is worse because they may be saying something which is the opposite of their testing.
But wait! There is one caveat that the PU / PP fan is not mentioning. When Pennzoil say cleaning, they refer to piston cleaning!
But here we have folks who are only interested in the area under the valve cover.
So even their definition of cleaning is not the same as Pennzoils!
But of course, they know something of Pennzoils "mystical" cleaning powers that has eluded the rest of us when looking at the PQIA comparative VOAs.
The lack of critical thinking here is priceless. The desire to want the world to be black and white when it is not is so great that black and white thinking is forced onto even relatively simplistic scenarios. No wonder this country is going downhill.
Carry on with the circus!