Mine have no decreases. The cables work almost like ribbing to give just a little bit of stretch, but resist stretching enough to keep the sock fairly tight. Plus, the higher up on the calf the sock goes, the diamonds "turn" sideways, in that they stretch that direction, so it looks like they've been knitted differently. That's not a very good description, but you get the idea. I'll post pictures to show what I mean.
I like the idea of a "knit-along". We could motivate each other to get those UFOs off the needles!
By the way, I can PM you the pattern, if you'd like.