It is a low ceremony process that surfaces hard to find dependencies in a code base. I use it when I restructure big and small chunks of code that I either can't fit in my head or can't finish in one sitting. You can use it in an Agile context or pretty much within any other software development process. It works best though with short feedback loops.
Legend has it that if you rub the right tiny ad, a genie comes out.
Devious Experiments for a Truly Passive Greenhouse!