Group discussions are often like pushing a rock down a hill. The bigger the group, the bigger the rock. It can take a lot of energy to get a big rock rolling, but it will eventually pick up speed and move on its own momentum. Of course, at that point, you can't control where it goes.

For some problems, the distance to a solution must be measured in days, not hours. It might take only a few hours of work, but if you try to work those hours all in a row, you won't solve the problem.