Certified GKH Gardening Expert
This is not recommended by most gardening experts because it can kill the tree. But quite a few home gardeners have reported that they've cut off the tops of their ponytail palms, either close to the top or close to the base, and that they did see re-growth. Some people saw pups at the base and others saw new shoots from the cut top. Others successfully planted the cut top.
Here is more advice about pruning ponytail palms for future reference: