A neat trick with satin stitching is to move your needle position full right to create a near perfect miter. These samples were stitched with feed dogs to demonstrate applique stitching.
In the video from Taunton Press Pancho Martinez is using an industrial Juki embroidery machine to free motion embroider flowers. It is very similar to the Bernina 217-50 that I use. He is using his knee to control the needle width. There are no feed dogs - so the stitch length is controlled by how slowly he moves the hoop. And! he has moved his needle position so that the needle swings randomly (actually he is controlling how far the needle swings) on one side and comes back to the same line on the other side.