When last you saw the shawl, it was happily admiring the mountain lake and for a week, you watched the shawl progress.

The Shawl Tale--the Prequel:
It was cast-on in NYC. I knit a few repeats while traveling north on the way to a mountain vacation but around Albany, NY, I decided the fabric created by using size 5 needles looked like saggy upper arm skin.
I then ran into a yarn shop in Saratoga Springs, NY yelling, "This is an emergency! You're the last outpost of civilized knitting before we enter the North Country and I need size 4 needles."

Size 4 needles were purchased. And, because they were there, size 6s too. Both Addis lace.
I then cast on (without frogging the size 5 saggy thing) the size 4s and spent vacation knitting away.
UNTIL
on the last day of vacation, I looked at the fabric and thought that it was too dense, too tight, too small just too. . . too. . .
So I went back to knitting on the piece first started on the size 5s. Decided that the saggy upper arm really was the look I was aiming for. But that it would look saggier and better
IF
I continued knitting it on the size 6 needles.
It's now post-vacation. Last night, I compared the size 5/6 fabric with the size 4 fabric.
That's the 5/6 on top and the 4s on the bottom. Yes, really it is. I've checked and re-checked.

What the. . . ??!! The fabic knit with the size 4s appears to be looser and saggier.
How did this happen?
Maybe more relaxed during vacation = looser tension?
I'm now in a quandary and am wondering:
Size 4s to size 5s for a couple of repeats to size 6s for half. Continue the other half on 6s. Pretend to be on vacation. Run water and have hubster quack like a duck. Graft the two pieces together. Ends will match. Blocking may even things out. Or not.
Anyone have a better ending to this tale?