Empirical studies of online debate almost universally observe a “dominant” minority of posters. Informed by theories of deliberative democracy, these are typically framed negatively—yet research into their impact on debate is scant. To address this, a typology of what we call super-participation (super-posters, agenda-setters and facilitators) is developed and applied to the http://www.moneysavingexpert.com/ forum. Focusing on the first of these, we found 2,052 superposters (0.4%) contributing 47% of 25m+ posts. While superposters were quantitatively dominant, qualitative content analysis of the discursive practices of 25 superposters (n=40,044) found that most did not attempt to stop other users from posting (curbing) or attack them (flaming). In fact, in contradiction to the received wisdom, super-posters discursively performed a range of positive roles.