Brainsurfing! That means: first write down your own ideas individually. And only after that, do it together or with a group. This is what Bo Seifert (again someone I met at ECCI) recommends. I recognise this from my own work. When people get the time to think for themselves first, they use their own knowledge and they use what they think is important. This is in line with recent research on knowledge sharing that showed that knowledge sharing works better when people bring in the knowledge or ideas they have and that others might not have. This research also showed that people do not usually facilitate each other in bringing in this knowledge. Brainsurfing is an easy way to make a start with it.