Not a clue what went wrong, I only posted on the gallery because it was an exciting pattern and due to the warping and damage quite difficult and fun to turn, which was lucky as you caught that I had a stray piece of wood, which I should have recognised myself, but because it was in that batch I convinced myself I had an unusually interesting piece of horse chestnut.
I turned another which was round, had enough depth to get a traditional curve to the edge and quite a good mix of sap and heart wood, nice bowl, but very easy to turn, and to my eye boring in comparison!