Hi Am I missing something, no idea what this method is.x
Welcome to the Quilting Board!
I've tried it a couple times and I like that way. I prefer raw edge for most applique(just because I want to see the fraying...my person preference).
enjoy your life...it's the only one you have!!!
even better use Solve' or any wash away product so that once you have sewn slashed and turned the use glue stick to place and sew then when your project is washed no bulk, and nothing to peek out and show.
I've used the fusible interfacing wrong sides together and then cutting slit to turn the piece. It can then be ironed to background and it hold until you sew it down. It may take longer this way but there's no edges to turn and the piece is softer than the fusible web.
I've used this method for years and love it. I don't particularly like the "stuck down" look of fusible webbing. By having the edges of my applique pieces already turned, it gives me a more traditional applique look. I usually hand applique these pieces. I only use my sewing machine to applique if it's a pattern that I can download to my embroidery machine.
I did a sun bonnet sue, actually 3, using this method
I have used the interfacing method for applique, one a wall hanging of pansies, some quite small (and leaves) and had no problems if you use your needle to keep the interfacing under control if edging by hand. I haven't attached the pieces by machine as I enjoy hand applique best. Another thing you can do with this method is to put a small amount of filling into the piece to give a more dimensional look to you applique. I actually had never seen or heard of it and was just one of my experiments - was a bit of a let down to find others had already been doing it. L. O. L.