If anything the dough is too hard, not too soft.
But the real issue isn't the shape, it's the even th9ickness of the slices. I can't get the dough to roll out even thickness, and when I slice, they always comes out thinner on one side than the other. The result is that part of the cookie over bakes.
I have not tried a mandolin using rolled up dough. I might try that if I can find a cheap enough one to try it out with. I think this dough might be form enough.