Thanks, but I don't really see how these articles support the claim that their ad network is more efficient. As you note, the first article has a single anecdata point about it actually being 10-15% worse, while the second one basically says 'trust me bro'. Also of note from the second article is the fact that the ad spend would actually increase.
Of course, if businesses are gullible enough to believe facebook when it fudges up some brand lift metrics without having a real impact on conversions, that's their choice. Trusting facebook to report any analytics is how you take your business behind the barn and help it pivot to video. https://en.wikipedia.org/wiki/Pivot_to_video
Could you please provide any sources for this claim?