Being Out of Sync in a Group Meeting

I was just in a meeting that I was leading where, almost every time I spoke, someone else spoke at the same time. The other person would continue speaking and I would stop. It was as if my timing was wrong; I was out of sync with the group. I imagine there were a number of things going on. One is that I was holding the list of topics to talk about as if we needed to get through all of them in the time we had, while the group wanted to savor and speak to each item at length. But it wasn’t just that. Within a topic, I was always bumping against someone else, timing wise. It felt awful. Any ideas or comments about this phenomena?