Warning: Spoiler! (Click to show)
First could be colors. I also like the way the SC looks almost like outerwear. I also like the slightly short sleeves, the slightly boxy jacket, and the way they both look with the cuffed trouser. Silhouettes and proportions, then. I tend to like what AAS posts, though - and since I don't know a thing about CM, most of my reactions are pretty knee-jerk. I would say that I like this outfit because it "looks plush and chunky and sharp all at the same time."
The only thing I'd change is the shirt - for a barrel cuff (this is term, no?), because everything else about the outfit looks really casual and easy to me; but maybe the links are there because there's a peak lapel involved?
Cheers. I don't rag on AAS because he's/your a good sport and helps keep the thread interesting, even if I sometimes think that he/you looks like he got dressed in the dark at a vintage thrift store in the Scottish Highlands. I liked the restrained color here, but it's still Postmodern IMO - a camel DB SC with leather buttons + lapel pin is FU and casual; a white shirt with FC's is unequivocally formal. The matching tie/PS looks studied. AAS isn't going for 'good taste' tho, so I don't mean it as a crit.
AAS could be the future, for all I know.