Yes, Brad, as usual, has it right. Simply think of splitting, rather than cutting, along the red line in your first photo.
I highly recommend parallelogram shaped cleats such as shown in the Triangle Strings article. I make mine with an even more acute angle. Not only does it reduce the stress riser along the line of cleats, but it also makes it easier to arrange them in areas where there are a lot of cracks close together such that everything is reinforced without having weaker areas between cleats, aka stress risers.