Seam allowance was added when the patterned was traced onto the fabric. 3/8 inch looks so small when I'm used to seeing 1/2. There is no seam allowance on the bottom or sides of the tabs, the neckline and underarm, or the shoulder straps.
The Toile is not flimsy, but it's not the tightest weave so I thought I should beck it with something to help stabilize it and also prevent any show through of the denim. This is the cotton voile (Or is it batiste, what is the difference? And this also came from the fabric stash.) that I affixed to the back using Sullivan's Quilt Basting Spray.
I don't expect it to completely "eliminate tedious hand basting and pinning" as the label claims, but I do think it will help hold the thin, floaty voile in place while I baste.