Must admit I'm quite surprised that Spin training is not part of an FI rating as they are probably the most likely people of all to find themselves in that situation!
Why would that be? Many more students and low time PPL holders get lost (navigationally) than they enter spins inadvertently, so statistically, I should have gone lost quite a few times over the years. That didn't happen. It's an important part of my job to watch over the actions of my students. By doing this, I can prevent them from entering spins. And I am not aware of any (unintentional) spin-related accident during training flights with an instructor aboard.