The mockup of the shoulder cape went well... even when I decided I wanted to add a high collar with detailing from an Emile Pingat 1895 cape in the Metropolitan Museum of Art (http://www.metmuseum.org/Collections/search-the-collections/159021).
The actual dupioni wasn't as painless to work with as I'd hoped. It was a piece from a Hancock Fabrics sale, so it had enough slubbing to almost make it look striped when I put the pieces together. That didn't thrill me, but it was already cut, so I hated to waste the fabric.
I'd also cut a pure full circle and probably should have made it slightly oval, because the length difference at the side seams really bugged me. I swear it had hung more evenly in the mockup. I'd been hoping for wrist length, but I know I'm going to end up hemming it up to the shortest points, which will make it elbow length.
And the collar tucks went in beautifully in the cotton mock up but gave me fits when I tried to recreate them in the silk.
Not sure this is going to be a finished garment that I am even the slightest bit happy with.