I've never done a back stripe, but I did some research a while back. I did unearth the fact that Martin used to just butt the back plates against a strip of herringbone and glue the whole thing together making two joints instead of one. This is an alternate way to do it without jointing and then routing. Just butting the strip in seems to me to double an already weak join, but it worked for Martin and they knew what they were doing. I suppose with back bracing and joint patches there will be no threat of failure. Don't know if they still do it this way.