I'm not sure if human beings are capable of reasoning about issues without taking positions on them. Without some sort of "bottom line" in our heads, brainstorming becomes very difficult. At least that's the case for me. So I don't think that the advice to avoid taking positions on ideas is helpful. I prefer the opposite approach: take many many many positions on ideas, have multiple sets of beliefs which you use to evaluate ideas with, even if those ideas have conflicts between them, and then weigh all the merits and disadvantages of the beliefs against each other. Committing to all ideas you can think of and committing to none of the ideas you can think of both avoid the problem of getting trapped in a flawed position, but I think the former is easier to do and lends itself better to creative thought and investigation, while the latter makes it difficult to cultivate curiosity.