There is much that can be learned taking apart something that you've built, just as there is much to be learned doing something perhaps that's never done or built in the first place.
Creativity, even deconstructive creativity, is a learning process and will almost always involve a certain degree of risk.
The kids at Amherst Island learned some valuable building lessons building walls with potatoes at this year's festival. The reward of play-building, the thrill of experimentation and the sense of accomplishment far exceeded the risk of disappointment or failure.
So too, the rewards for those happy men and women creating with stone at this year's festival far exceeded any risks of setbacks, criticism or concerns about exploring (or being taught) less conventional approaches to building walls without mortar.