I knew there had to other ways to help these GDI engines stay cleaner. Thank you Buster for finding this.
It seems my former Valvoline Advanced Synthetic 5w30 did a good job of maximizing suspended combustion contaminants.
I'm expecting to see the same - or better, from Valvoline Modern Engine.
My 2.4 GDI engine has seen factory fill and Castrol Edge prior. But I only witnessed blackish cold start exhaust using the Valvoline. So I'm guessing my oil choices and continuing to use cellulose media filters ( which supposedly are best at capturing soot/carbon), are working well. My used oil at 4k (changed this week) was sooty also.
So the idea to get most of this carbon/soot out of my engine and some thru the exhaust, is working.
I know nothing about complex inner engine mechanics. What I see and observe - I comment on. Since I know absolutely nothing mechanically, I won't comment further inside this thread.