For testing purposes, I often need to add logic in a template for the circumstance where a user may not answer a y/n question. However, when I want to push a previously populated workflow into a new one, in order to test, there is no way for me to clear the answer in a yes/no variable so that it appears to be unanswered. Instead, I have to create a completely new workflow, which may require me to answer a very large number of required variables before I can even get there.
It would probably also be handy to clear other variable types as well. For example a multi-select where multiple boxes are selected and now you want to test for only 1. It would be easier to clear all the answers and just select one, than it would be to unselect multiple boxes.