What would take the reading off the table
Tests
A hypothesis that cannot die is not a hypothesis.
These are the load-bearing claims. Each sentence says what would have to be true for that claim to fall. The worlds themselves are on Sequence. The clock is on Cycle.
One disk, one time
If Io through Earth formed together, in the orbits they now occupy, as first-generation bodies of a single disk, the sequence comes off the table.
Native ice and rock
If Europa through Triton are ordinary outer-system ice and rock, assembled where they now sit, with no volcanic predecessor, those stages come off the table.
The beginning under the weather
If Jupiter’s Great Red Spot is only air all the way down, with no extra mass under the weather below about 100 bars, this beginning comes off the table.
A quiet lid that was never grooved
If Callisto is a cold first-generation ice moon that never had to pass through a grooved Ganymede, Stage 4 comes off the table.
Air that always belonged to Saturn
If Titan’s nitrogen column and methane weather have always belonged to Saturn, with no quiet ice-lid predecessor, Stage 5 comes off the table.
Frost that is only a captured KBO
If Triton’s nitrogen ice and plumes are only seasonal frost on a captured Kuiper body, with none of Titan’s volatile family left on the lid, Stage 6 comes off the table.
A stagnant lid that cannot come first
If a mobile-lid Earth cannot follow a stagnant-lid world of Mars’s class, the last rehearsal comes off the table.
Continents that cannot follow
If felsic continents are unique to a first-generation Earth and cannot follow a Mars-class lid, the Mars-to-Earth step comes off the table.
Spent worlds that were never Earth-class
If Venus never had oceans or continents, and Mercury was always a small iron world, the prior-cycle remnant reading comes off the table.