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rememberThe takeaway: what to remember
figureThe number that matters
evidenceThe evidence line
rulingThe ruling
claimThe claim that fails
Each mark is drawn once, as you reach it. Numbers are only circled when they come from the story’s own figures.
01 / ProductsTrue, butFree sample
GitHub's famous number says Copilot users finished a task 55% faster. A Harvard paper tracking 718 firms finds AI agents raised lines of code 30%, while finished work showed no statistically significant change.
GitHub, research blog post (7 Sep 2022); tested at firm level in a Harvard working paper (current version 4 Aug 2026) ·
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GitHub's 2022 post says developers using Copilot finished a task 55% faster.
The reality check
That task was writing one HTTP server in JavaScript. A Harvard working paper using 300 million work events across 718 firms finds AI agents brought a 30 percent increase in lines of code, but the resolution rate for issues and epics did not change in a statistically significant way. Review time balloons 49 percent.
Why care? When a vendor quotes a speed-up, ask what was timed. One timed task does not measure software shipped.
Take this with youGitHub's 55% speed-up timed one coding task. Across 718 firms, AI agents added 30% more code but no statistically significant rise in finished work.
Open the evidence4 source pages +
The claim we checked
Developers who used GitHub Copilot completed the task 55% faster than the developers who didn't use GitHub Copilot.
These are quoted receipts, not a count of independent investigations. Several reports may rely on the same original source.
A solo developer rebuilt Word, Excel and PowerPoint with Claude, the post says. The WordCraft README says it is about 60% of the way to replacing Word for real work, and the spreadsheet app says 50%.
Viral post trending on tech forums; apps published by ArtCraft (Brandon Thomas) on GitHub, 7 Oct 2026 ·
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A solo developer rebuilt Word, Excel and PowerPoint as free open-source apps using Claude.
The reality check
The apps exist on GitHub, free, and DigitalToday reports all three were built with Claude. But the READMEs estimate WordCraft at about 60% of the way to replacing Word for real work, GridCraft about 50% ready, DeckCraft about 55%. Nothing in our record shows an earnings figure or user count.
Why care? The apps are real and free. By their own READMEs they are alpha software, about half to three fifths done.
Take this with youThe free, Claude-built Office lookalikes are real. Their own READMEs put them about 60, 50 and 55 percent of the way to replacing Word, Excel and PowerPoint.
Open the evidence5 source pages +
The claim we checked
A solo developer rebuilt Word, Excel and PowerPoint as free open-source apps using Claude.
These are quoted receipts, not a count of independent investigations. Several reports may rely on the same original source.
Ten minutes of AI erodes your ability to persist, Berkeley's headline says. The study measured skipped problems on a paid online task, three test problems each, and its largest trial found the skip gap was not significant.
Berkeley News (UC Berkeley), headline on a 9 Oct 2026 story about an arXiv preprint; reached the Hacker News front page ·
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Berkeley News headlined that using AI for just 10 minutes erodes your ability to persist at hard things.
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we find that although AI assistance improves performance in the short-term, people perform significantly worse without AI and are more likely to give up
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