I think what might be confusing some is the order of the last two pictures are reversed. In other words the finished block is shown before the sub-block being squared up. The finished block is four squared up sub-blocks. The sub-blocks are made up of two pieced strips plus 2 triangle pieces. The other thing that initially confused me was the red fabric. Apparently the grayish red fabric is the wrong side of the red fabric. I also agree that the line drawn on the one square should be going the other way.
The size of pieces used would help clarify it but with a little bit of thought you could get things sized.
The one link listed (the one listed on quilt board) it appears broken. I don't know if anyone else is having this problem. If this is a copy-write protected technique then perhaps that is why the link has been removed.