Thornfold

Evidence

How we decide what is true, and what we do when we are wrong.

Most of what the SEO industry repeats is not in the documentation. This page is how we tell the difference, and how you check us.

01 The source ladder

Every factual claim in every resource must trace to a Tier 1 or Tier 2 source, and the class of each source is printed inside the document, so your client can weigh it themselves. Official documentation and a named employee’s statement are different kinds of evidence. We never blur them.

The source ladder: what each tier of source is, and how we are permitted to use it.
TierSourceHow we may use it
1Official platform documentationCited freely, quoted exactly, always with the date we read it.
2A named platform employee’s statementAttributed by name and date. Never presented as documentation.
3Large-scale studiesLabelled third-party, with sample and method. Correlations, never causes.
4Industry publicationsEvidence that a statement was made, not that it is true. We trace to the primary.
NeverUnsourced vendor blogs, content farms, “guaranteed rankings” pagesNever cited.

02 The corrections record9 to date

Corrections are published, not silently patched. A visible corrections record is the only available proof that the review process is real. Each names the resource, the version that carries it, and what changed. Every resource also carries its own version history inside the package, so a buyer can see the record without leaving the document.

  • Why SEO takes time

    1. 2026-07-14 · v2.0

      Source removed. This guide previously pointed to a 2017 Google video as the origin of the SEO timeline figure the industry repeats. We could not verify what that video actually says: its audio cannot be checked automatically, no transcript is published, and our own record of who had verified the wording turned out to be unsupported. So we removed the video, the estimate taken from it, and the claim that rested on it, rather than keep evidence we could not stand behind. What remains is what Google publishes in writing: no universal timeline, and no guaranteed ranking.

    2. 2026-07-13 · v1.3

      Citation address corrected. Google removed the 2017 “How to hire an SEO” video from its written hiring guidance, so the Maile Ohye statement is now cited directly to the video on Google’s official Search Central YouTube channel. The written guidance names no timeframe at all, which is the guide’s own point and is now recorded in the source register. No claim changed.

  • What we can and cannot control

    No corrections to date.

  • Why Google rankings fluctuate

    1. 2026-07-14 · v2.1

      Source record refreshed. Google revised its local-ranking help page: the lead sentence now says results are “mainly based on relevance, distance, and popularity” while the page’s own factor definitions still name Prominence. The source register now quotes the current factor definitions and records the inconsistency. The guide’s explanation of the three factors is unchanged and remains supported by the page’s definitions. Quotation marks were also added wherever the guide uses Google’s exact wording.

    2. 2026-07-13 · v2.0

      One wording correction: the position-metric summary now carries Google’s full recommendation (change over time, especially sudden changes, alongside the absolute number). Also in this version, clearly an addition rather than a correction: a new page covering what Google documents about AI features: how links inside AI Overviews and AI Mode are counted, and why the results page changing shape moves numbers on its own.

  • What happens in the first 90 days

    1. 2026-07-14 · v2.0

      Source removed. This guide previously pointed to a 2017 Google video as the origin of the SEO timeline figure the industry repeats. We could not verify what that video actually says: its audio cannot be checked automatically, no transcript is published, and our own record of who had verified the wording turned out to be unsupported. So we removed the video, the estimate taken from it, and the claim that rested on it, rather than keep evidence we could not stand behind. What remains is what Google publishes in writing: no universal timeline, and no guaranteed ranking.

    2. 2026-07-14 · v1.3

      Source record annotated. Google revised the lead sentence of its local-ranking help page. The sentence this guide relies on, that businesses with complete and accurate info are more likely to show up, is unchanged and was re-verified. Quotation marks were added wherever the guide uses Google’s exact wording. No claim changed.

    3. 2026-07-13 · v1.2

      Citation address corrected (the same 2017 video statement, now cited to Google’s official channel), and one wording correction: the position-metric summary now carries Google’s full recommendation: monitor change over time, especially sudden changes, alongside the absolute number.

  • Six SEO myths your client believes

    1. 2026-07-14 · v2.0

      Source removed. This guide previously pointed to a 2017 Google video as the origin of the SEO timeline figure the industry repeats. We could not verify what that video actually says: its audio cannot be checked automatically, no transcript is published, and our own record of who had verified the wording turned out to be unsupported. So we removed the video, the estimate taken from it, and the claim that rested on it, rather than keep evidence we could not stand behind. What remains is what Google publishes in writing: no universal timeline, and no guaranteed ranking.

    2. 2026-07-13 · v1.3

      Citation split on myth 3: the 2017 timeline statement is now cited directly to the video on Google’s official channel, and the written hiring guidance (which names no timeframe and carries the no-guarantee sentence) is cited separately. Every quotation re-verified verbatim; no myth’s substance changed.

03 What we refuse to print

  • A ranking, a traffic number, a revenue figure, or a date. Nobody can guarantee them. A document that pretends otherwise is worth less than nothing the moment you put your name on it.
  • Insider knowledge of any search engine’s algorithm. We have none, and neither does anyone selling it to you.
  • Uncited efficacy statistics, including about our own products. We will not tell you this saves you three hours, because we have not measured it.
  • Testimonials, ratings, client logos, or sales counts. We have none, and we will not invent them.

04 How these are made

Research and drafting are AI-assisted. Every factual claim is checked against a primary source and recorded in a claim ledger with that source, its class, and the date it was read. Before anything is published, a human owner reads the text that ships and signs it off. We tell you this because the alternative, letting you assume otherwise, would contradict the only thing we are actually selling.

What we will not claim is that a human has personally re-verified every claim against its original source. That is a stronger promise than our process makes, and this page used to make it. We found a claim whose verification record said a person had checked it when no person had. We removed the source and the claim rather than keep evidence we could not stand behind, and it is in the corrections above. The check that failed is now automated, and it runs on every build.

The review schedule, in detail

Every resource names its sources and the date we last read them, inside the document itself. Dates are meaningless unless honoured, so the review schedule is published per resource and shown on its page. Volatile facts carry a shorter cadence than structural ones: how search works changes slowly; what a specific documentation page says can change any week.

What we do not claim about accessibility

The delivered PDFs are tagged, declare their language, and carry bookmarks, and the editable files use real heading styles and describe every diagram. They are not certified to PDF/UA, PDF/X, PDF/A or CMYK. Those are formal standards requiring validation we have not performed, and we will not claim a conformance we have not proved.

See every source we cite