These things really do eat up fabric don’t they?
I had hoped to handsew the whole thing, but I’ve been having bad RSI-ish feelings in my wrists for a few weeks now, and hand-sewing four 40″ french seams sounded like a bad idea. So, I machine sewed the french seams, the bottom hem, and most of the top hem. The gores I did all by hand, since I’m not good enough to control the pointed end of the gore by machine.
It *is* possible to flat fell a gore as it turns out. Decide on a starting point where one fabric will fold over the other. I went with the point of the gore, since obviously only one of the sides had enough fabric to fold over a hem. From there you can just go around the gore to figure out which seam folds over the other.
Of course, I hadn’t decided I was going to flat fell these seams until after I had already sewn in the whole gore square, right-side-to-right-side, which means my flat fell seams are technically the wrong way.

Normally the folded seam allowance shows on the outside (like the side seam on jeans), but here the fold is on the inside.
Oh well, anyone who can see my camicia well enough to examine underarm gores has already gotten me out of my dress, and by that point they better have better things on their mind than examining my sewing technique, ya think?