For our pairing session, Alistair and I did many dry runs, writing the code test-first for the problem we had selected. We did multiple dry runs as a pair, and individually. I find it interesting that every time we did a dry run, it was different--our conversation and the resulting code.
When we wrote the code during our first presentation, it went down a course quite unexpected from our dry runs, and very different from the second presentation. We are planning to give that presentation at least a couple more times, and we have discussed improvements.
I suspect that what is true for our test-first coding sessions will be true of our presentations. You will never get the same audience twice. You will never do the same presentation twice.
For complex collaborative tasks, repetition leads to refinement, learning, and innovation.