THE CLAIM. Grok 4.7 'will exceed all current models', with a SpaceX engineering corpus so strong Musk 'would be shocked if any model is better at real-world engineering than 4.7'. Reported size: about 2.1 trillion parameters. Timeline: '3 to 4 weeks'.

THE CHECK. every part of that is a promise about an object nobody outside xAI can touch. No benchmark exists, vendor-run or otherwise, because the model is unreleased. The 2.1T figure traces to Musk's remarks and appears on no xAI specification sheet. The training-corpus advantage is unfalsifiable and comes with its own asterisk in Musk's earlier post: the SpaceX data excludes everything ITAR-restricted, which is precisely the rocket-engineering core the sales pitch evokes. And the one checkable element, the calendar, has already failed once mid-claim: on July 25 the model was 'about four weeks out', pointing at August 22; on August 12 that became '3 to 4 weeks', pointing at September 2 to 9. The desk notes the base rate: Grok 4.6 was framed for August 7 and shipped August 12. This is a pre-release superiority claim scored against a track record of sliding windows, which is why it files as UNSUPPORTED rather than wrong: there is simply nothing to check yet, and the claimant knows it.