Darcs theory of patches

The darcs theory of patches is about how to order and reorder changelists (not sets) so they can represent merges of various state versions. IOW the mapping between versioned changes and versioned states.

This document is worded in a messy way, I'm specifically confused about it saying that conflicts cannot arise at one place but I see it just wrapping conflicts into an atomic unit in another. This concept is interesting though, being able to version the conflicts and postpone resolution. Particularly because future versions may resolve the conflict anyway.