Well, surprise surprise. I had 5k on this oil when I changed it. The viscosity at 100 degrees C was over 11! But all the other numbers looked good, from wear to additives. No 0w20 has done that in this engine so I can't help but wonder what the viscosity was when it was new. I've got another 5 quarts in it now but will cut this run short at 3k. I'm going to go back to EP 0w20. I just don't like how thick this was. The 3.6 is really easy on oil, so I can't imagine it thickened up from its rated viscosity to over 11.
Then there's the possibility of a mistake by Blackstone, but all the other numbers look good. Hmmm.