I have noticed a resurgence of interest in the diagonal pinhead stitch. I did a small tutorial on The Diagonal Pinhead way back in 2010. It's funny how these things re-emerge every few years as if they had just been invented. When I did my post in 2010 I had made the technique up for myself but I don't for one minute think I invented it. it will have been thought of before and no doubt been used since the first crosses were ever put into fabric.