Here is another video from Heirloom Creations and there is a connection to their blog on the previous video.
This one shows a lovely finish to a quilt with a 3″ wide finished binding using double thickness fabric. This would require 12 and a half to 12 and three quarter inches – an awful lot!
An alternative could be to cut the binding material to 6 and a half or 6 and three quarters, sew a quarter inch stitch line along one long edge and attach the other long edge to the quilt as the video shows. The stitched line then gives you an easy reference when attaching to the second side.
This binding method would work equally well with our usual habit of machining the binding to the front and hand hemming it to the back.