I've looked through your trial debates, and realised that many of the groups had not quite managed to engage in a proper argument. Hopefully this is due to the limitations of the environment and reduced interaction with the electronic debate. Regardless, I hope that there have still been some takeaway lessons from this.
1) Working with your team - Hopefully this chance of splitting the work has given you an inkling of how to divide the research/preparation for the actual debates.
2) Planning your debate - Somewhat related to the earlier point, but you'll need to think about what points you expect to make during your oral debate, and preferably pre-empt some of the opposing team's arguments and prepare rebuttals for them.
3) Generating rebuttals - Some of you might not have got to this stage, but it is quite an experience to hear an unexpected point from the opposing team and attempt to generate a response on the fly.