In the tutorials, you can teach people to use AI symbols and PSD smart objects instead of making copies of objects.
If you're creating face positions, you're copying some elements (like eyes and mouth shapes) a lot. If you then want to tweak such an element, you have a lot of work. With Illustrator Symbols and Photoshop Smart objects, there would only be one design and several instances. This is great if you want to copy-and-change a puppet to create another puppet too: no longer redesign the eye 14 times, just change one and all the instances in the head positions update!