[EM] Further SODA refinement

[Jameson Quinn]

Problem: "Near-clones" A1 and A2 have both put each other at the top of
their delegation order. Their totals, combined, constitute a majority, but
either one alone would be beaten by B. Both insist that the other one
delegate, threatening to refuse to delegate. It's a game of "chicken", and
the more symmetrical the situation is, the more likely that negotiations
fail. Even if they succeed, the winner may simply be whichever is more
intransigent, not a good result.

Solution: When choosing whether to delegate, candidates do so not
"simultaneously" but sequentially, in order from most delegable ballots to
least delegable ballots. This means that candidates with fewer delegable
votes are unable to "make ultimatums" to candidates with more delegable
votes.

Three sub-scenarios:

Assume all votes are delegable (for simplicity). Assume WLOG that A1 is the
one with more votes. Note that if this is a 1-dimensional ideological
spectrum, that is likely to mean that A2 is the "squeezed" Condorcet winner.

Scenario 1: B prefers A1.
B does not delegate, hoping that A1 and A2 will be unable to negotiate. A1
does not delegate, as an ultimatum to A2. A2 is strategically forced to
delegate if they don't want B to win.

Scenario 2: B prefers A2.
B delegates to A2, knowing that otherwise the equilibrium is an A1 win. A1
and A2 do not delegate. A2 wins. Especially if the voters are ideologically
divided, we can assume that A2 was the CW.

Scenario 3: B prefers neither, or marginally prefers A2 but decides not to
delegate (hoping for a win).
Results are the same as scenario 1. This is perhaps a "good center-squeeze"
scenario. That is, if there's an approximate 1-dimensional spectrum, chances
are that A2 is the centrist candidate and thus the "ideological CW".
However, B's choice not to delegate to A2 reflects on A2's quality. Perhaps
SODA, here, has avoided a "mushy middle" win which a Condorcet system would
have fallen into.

Note: If B adopts a "worse is better" attitude, trying to elect the one of
A1 or A2 who will be a weaker opponent in the next election, then they
probably can. However, they must do so openly, so hopefully voters will see
through whatever they use as a rationalization and punish them for their
selfish actions. It is essentially impossible for a good voting system to do
any more than that to avoid such anti-patriotic behavior.

....

Note: I got essentially no responses to my last message refining SODA (where
I suggested a 5% minimum cutoff to be able to actively delegate votes, with
votes below that delegated automatically). Is that just because nobody had
anything to add, or are people not interested in discussing this system? If
it's the latter, I'd love to know why not.

JQ
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