Karen, I see your point, I really do. And when you AND Ann Rowley tell me that you would probably pack it in, I know to proceed at my own risk. What I've decided to do is tackle this as a longer-term project -- a kind of pattern-fitting exercise, and abandon any idea of a quick wearable garment. Instead I'm working on some trousers alongside it and I'll basically just continue with my 6PAC sewing and work on this when inspiration strikes.
So, yesterday before my interview I unpicked the vertical seams and the zipper up to the yoke. I did not forget about what Ann R said, I just decided I would have a look at what I found after letting the pieces stretch somewhat.
This morning I did some pinning. I decided that IF I could salvage it I would have to have side panels or gores or something. so I pulled the panels up on the CF/CB until the edges met and hung straight. It's about a 1/2" tuck, and I pinned that, and then pinned the CF/CB. At the bottom, the panels overlap somewhat - perhaps 1" beyond the seamline?
Then I had a look at the side seams, and discovered I could pin those seams down to hip level without noticeable distortion. Below the hip I would need to insert a gore, about 8-10" wide at the bottom. Fortunately I do have enough fabric to be able to do that.
Here are some pictures of the unpicked skirt pinned on to the dummy.
Front:

Side 1:

Side 2:

Back:

My next challenge is how to mark these new seamlines. Also, of course, I certainly will have to unpick the yokes. And then once that's done it will all need to be basted on again and refitted - on me, not the dummy.
Since every bias fabric has a different drape, is there *any* point in my redrafting the pattern to include the gores in the original panels, I wonder?