does not measure the bot
Seven decisions. Two are not what T03 expected, because the review moved
the ground under both.
D1: strategy fusion DOES NOT APPLY, and that is why the affordable option
is also the honest one. Fusion is a defect of aggregating over
determinizations to choose a move -- the search picking different actions
in states a player cannot distinguish. After the game there is ONE WORLD:
the deal is known, so a search over it yields a line executable in the
only world there is. The survey treated fusion as this pass's central
obstacle; it is an obstacle to a playing engine, which we are not
building. The tool answers "given the deal as it actually was, was there a
line that reached the threshold" and is labelled that way on screen --
never "how you should have played".
D4: difficulty is the WINNABLE FRACTION, not a bot's win rate. C4 killed
the bot rate -- two trivial policies span 0-100% on the same deals, and
improving the bot would make the game "easier" without a rule changing. A
measure that moves when the measurer improves is not measuring the thing.
The solver supplies the alternative: over N deals, in what proportion does
a winning line exist. That is a property of the deal distribution and the
threshold, which is what ground-game tunes and what GROUND-WP-0005 is
blocked on. Ships as a table -- winnable fraction, named reference policy,
skill gap -- never one number, with policy/N/seed-range/K in the number's
name. Stated as a LOWER BOUND, since a K-round search cannot see a line
that needed round 1.
D2: search GroundState. The survey's view-only structural boundary is not
implementable -- a view cannot fold events, and it said so in §6. The
guarantee moves to something checkable: every move in a witness is marked
visible or hidden, computed from project(). A witness reads "you could
have won, but two of these six moves needed a card you had no way to know
was coming" -- more useful than either extreme.
D3: bounded exhaustive over the last K rounds, table as one co-operative
agent, K=2 default. Affordable once C6 corrected the premise: joint
branching over the last two rounds is ~5x10^2 / 1.6x10^5 / 5.7x10^5 at
2/3/4 seats. Wording is normative: "no winning line found in the last K
rounds", never "unwinnable". PIMC and ISMCTS rejected -- they add strategy
fusion to a problem that does not have it.
D5: the harness becomes an instrument before any figure is quoted (C3) --
positive controls, --self-test in make self-tests, a make target, and a
PLURAL policy panel, because the spread between policies is what C4
exposed and hiding it would restore the error.
D6: no new crate and no port. The L declaration was an over-declaration
and is recorded as one. D7: the node cost is disputed 5x between author
and reviewer; T04 benchmarks it with criterion and neither existing figure
may be cited, including by this ADR.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>