A model lists sources by rank rather than by number: a real answer sent [2][1] for
a sentence resting on both, and once the digits sit next to each other that reads
as "two, one". A run is now a set of sources ordered ascending, so the same run
draws as the first two sources rather than as a puzzle.
The numbers themselves are still never renumbered. [3] remains the third source
the turn found, whether or not the answer cited the two before it, so the list and
the marker still agree.