There are a couple of things I learned from making swants.
First, I am now quite good at the mattress stitch, a stitch I had not needed until now.
Second, yes, having a good friend help out on the rear shaping is pretty vital. I would like to note, however, that it should be a "good" friend and not someone you would feel shy about since their hands are all over your rear flap. :)
Third, in his instructions he mentions folding in the flaps and making a 90 degreeish angle. That was the key in the shaping that I missed the day before. You should start with the outer hip point and make a line to the center of the crotch. I also made the crotch seam in the back another inch or so because that's just how it worked out.
Here's a picture and notice how the seams kind of make a "v" from the outer hip to the crotch seam.
I hope this helps and here are some goofy pictures of me testing out the flexibility and comfort of my new swants. I will also make a waistband and add some elastic, but that's for another day.
