Does this person feel playful or irritated?
If you said irritated, you aren't as likely to raise the collective intelligence of a group.
It is a truism that the smartest of all of us is not smarter than all of us, but how much smarter all of us are depends on how we work together. Ecology lives and breathes by group efforts these days--very rarely are papers ever published by a single author. Yet, we have paid scant attention to how to put these groups together and what makes them successful.
A paper last fall in Science actually did experiments to test what factors made groups collectively the most intelligent. The authors assembled a large number of working groups and had them together try to solve a series of complex tasks.
What made some groups the most successful?
It wasn't necessarily how smart the smartest person in the group was. Instead, collective intelligence correlated best with "with the average social sensitivity of group members, the equality in distribution of conversational turn-taking, and the proportion of females in the group" state the authors.
Not all the lessons transfer directly to scientific working groups. The tests the authors used were generic for which there might not always be specialized knowledge--like playing checkers. Deciding sampling strategies or statistical analyses is going to depend on having experts a lot more than checkers does. That said, there seem to be some pretty good lessons from the study. Take turns. Listen to others equally. Have women involved--or at least men who behave like women in the sense they are "socially sensitive". Not sure what that is? Take this test. Didn't score well? Then it's probably even more important to have women involved I would guess.
Woolley, A. W., C. F. Chabris, A. Pentland, N. Hashmi, and T. W. Malone. 2010. Evidence for a Collective Intelligence Factor in the Performance of Human Groups. Science 330:686-688.