Posting a link to my favorite thread on herehttps://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4853520/2
middle of page 2 .. old study but still...
Here are the results. 600 ppm dinuclear moly with ZDDP (Blend 5) did best both in friction and wear. Note that it has the highest sulfur with 2,000 ppm (0.2%), which is at the ACEA C1 and C4 limit and close to the C2, C3, and C5 limit (0.3%).
So a healthy dose of good old MoS2 is proven to work. No placebo.
Dont expect miracles, sometimes it can take a lot of driving to notice any difference and if you take good care of the engine you may not notice anything at all.
Does not mean your wear/friction numbers arent better.
I also add a bit (10% of fill) of Magnatec Stop Start formula but thats just me.