Del, actually no, that's the area I thought it was gonna go! I would have preferred to follow the back far better in that area, but it split awkwardly and there was hardly any heartwood in that area. I was watching that spot the entire time but it looked pretty solid, surprisingly. It was about 5 inches from the tip in that area, so that may be why it wasn't as vulnerable.
I was thinking it looked dry as well, as soon as it broke. Weird though, as it was actually still wet in parts as I was roughing it out. It was kept outside the entire time, so couldn't have dried out too fast, and even 2 weeks ago I cut a similar sized piece from an offcut in half and the centre was still slightly wet.
I think just having that much variation in grain direction, and all the knots etc all focused in one place was probably the culprit more than anything else. It looked so good on the tiller though