The assertives do indeed "thrive" in the brain-storming environ, but generally, top-notch ideas aren't produced. You end up with the "best" of the "so-so" ideas bandied.
The elusive but coruscating, "ground breaking" idea will come from the silent loner of the group. Why? He/she's been thinking and pondering while the assertives are busy being assertive.
Try this: after the brain-storming session has convened, sit down and over a cup of coffee have a tete-a-tete with the reticent guy or gal for the really "great leap forward" idea.
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