I have had 2 quite different experiences of teamwork on H817. The first was when we produced a joint end-product early in the course. There is no doubt that mutual performance monitoring, back-up behaviour, adaptability and team orientation were very much in evidence. Funnily enough, I don't think we can be said to have had a leader, though different people took the initiative at different points.
Everyone was very adaptable - the direction and nature of what we were producing changed quite a bit as the project developed. There was no one who was so fixed on a particular approach that disagreement arose. For me, this adaptability was the crucual factor - people were ready to change course following discussion
On the MOOC a group of 4 of us actually produced an OER. We seemed to agree quite quickly on the overall topic though it took a while for the different parts of the content to emerge. There was not so much need for adaptability so most time was spent producing materials. Again, there was no official leader but one member got close to that role by virtue of the amount of work she did.
Both collaborative experiences worked because we trusted each other.