I will always demonstrate spins to students at some point in their training, but I make it clear it is a demonstration, rather than a full teaching element. Why? I think you can talk about spinning with her autorotations, inverted possibilities and this and that until the cows come home, and talk about recoveries in that too - Does it make sense to the student? I think not. Show them a spin, show them a recovery and it'll click. However, to become efficient and fully competent at spin recovery requires a lot more practice, which is why I demonstrate, as opposed to teach.
Some may argue that the demonstrations make your average PPL holder think they can cope with spins - From the expressions on their face, I can say no, and most return post PPL and ask for spin training or aerobatic training - And I'm happy to oblige!