That sounds very interesting, I have never heard of growing potatoes in straw. When we moved to our house, the previous owner planted potatoes in our gardens, for about two years we were seeing those potato plants growing again and again. I love that plant because it is very easy to grow and of course they taste great. Like you mentioned I know from my grandmother they used to cut potatoes with the sprouts on each piece and plant if. Thank you for your tip and hopefully you will have a great harvest!