As I was working the Progressive Shawl edging around the bottom point I added in some extra "ease". For roughly two pattern repeats just before and after the corner, I ended every other incoming row with K1 instead of the K2tog that would join it to the edge. I say "roughly" because, kiddos, I was winging it here. I didn't chart it out, and I didn't write down exactly how many times I did this on each side of the point. I'm hoping the blocking fudge factor godesses will be good to me.
If I ever get to the point of writing the pattern up, I'll have to be more precise. But if I go there, I think I'll be changing the pick up ratio for the border. The garter center is a little scrunched where it joins the stockinette based border. I'm still reserving final judgement until after blocking. But if my suspicions prove to be well founded, and the border numbers have to change, there no point in calculating an absolutely precise edging repeat here. (That's my story and I'm sticking to it.)