When I explain my Knowledge Café process to people, I make the point that it's okay to go off-topic and that “the question is only a seed. But I am often asked somthing like this:
“Doesn't that bring the danger of dissipation of the conversation or cause problems after the participants have changed the tables?”
My reply is that the Knowledge Café is not about trying to control people and what they say or talk about. It's about treating them as adults.
Real conversations go off-topic in everyday life – all of the time. That's the intrinsic nature of conversation.
If you try to control conversation – you destroy it. If the topic is meaningful to the participants and the right one – they will quickly return to it.
Going off-topic also allows issues to emerge that were not anticipated. This is at the heart of what the Knowledge Café is all about. You need the space to explore stuff and the freedom for people to relax and tell personal stories and share anecdotes.
Rather than dissipate the conversation – it keeps it natural and animates it.
And there is not a problem when people change tables. Any sidetracking in an earlier table discussion either dies or if it is important, it is built upon.
I explain this reasoning more fully in my blook on Conversational Leadership.