Great tute. That is how I do mine too. The only difference is that I sew my sleeve into the binding and then I only have to hand stitch the sides and bottom.
I sew the binding to the top. Then I pin the sleeve on and go over the seam again sewing the sleeve in place. When I turn the binding to hand sew it to the back, the sleeve is in place. (Does that make sense?) I hope so.