A further search came up with this quote from Amy Newman http://dancingwithelephants.ca/tag/enabling-constraints/
"In our teacher education module, we explored the notion of “enabling constraints. I discovered the term in the book, Engaging Minds. Enabling constraints are about opening possibilities by limiting choices.Very simply put, too much choice is overwhelming. Too little choice is restrictive, squelching learning and creativity. By giving choices in lesson activities and projects within a given structure we are providing enabling constraints."
Enabling constraints are not prescriptive; they don’t dictate what MUST be done, rather they are expansive, indicating what MIGHT be done… from Engaging Minds (2000), Davis, Sumara, Luce-Kapler, p. 193
When getting started out here in the desert, I had almost unlimited possibilities. Whenever I am faced with such an opportunity - I look for what I had previously called givens that guide me down a certain path. An example of this is: How big do I build my new house? My chosen constraints were based on budget, the size of dimensional lumber that is commercially available, and my thoughts on the minimum amount of space I needed to live comfortably. The constraints on my greenhouse were - I wanted to use 4 shipping containers to outline a courtyard...how I arranged them was based on the space available on site and an esoteric design aesthetic that I have embraced over the years. In everything I do, I look for things I know to guide me down an uncertain path.