Like most facilitators I have strong opinions on brainstorming. And like a lot of the soft side of quality, these facilitation skills can really open themselves to a criticism of the vulnerability of scientific claims and there is a fair amount of justification for criticisms of the pursuit of novelty over truth. Add to it that there is this major pipeline of junk psychological science and there are good reasons for challenging these opinions.
It is for this reason I do less and less brainstorming as a verbal exercise, and rely more on brainwriting as I discussed in the post “Brainstorming usually sinks your ship.”
In the article “Should we allow criticism while brainstorming?” by Dylan Walsh we are exposed to some research from Jared Curhan at MIT that shows when criticism should be leveraged in brainstorming exercises. Well worth the read.