Happy to, here one example where Grok 4 Fast, despite producing a fairly consistent pelican [0], did severely worse in a similarly outlandish scenario along with Haiku 4.5 and GPT-5 for context: https://news.ycombinator.com/item?id=45599403

> [...] a really great pelican riding a bicycle and then a terrible sloth riding a skateboard [...]

Happy to play ball. You made a blog post a few weeks back on one of the Qwen models with the eye-catching title "Qwen3.6-35B-A3B on my laptop drew me a better pelican than Claude Opus 4.7" [1].

Here is what Qwen3.6-35B-A3B via Openrouter provided for a sloth riding a skateboard: https://imgur.com/a/Dy8fvR5

Like Grok 4 Fasts attempt at a mushroom in a rowboat, it is barely recognisable as anything despite both Qwen3.6-35B-A3B and Grok 4 Fast having no issue with more popular (i.e. benchmarked) examples. Whether this is a case of training data being unsanitized or intentional benchmark targeted training, I cannot say, but it is the case.

And here is Opus 4.7, again via Openrouter: https://imgur.com/a/Qus1Enf

A massive delta in favour of Opus 4.7, despite the pelican Qwen3.6-35B-A3B produced being noticeably better as you rightly pointed out. What does that tell us? Whether intentional or not (with such deltas, I do have my suspicions), any eval with such a delta is clearly polluted and can not be a source of information, especially as its continued existence does hinge on you testing similar prompts in private as a sanity check, yet by your own admission never noticing the plainly apparent delta in quality. I specifically stuck with the skateboarding sloth too, to keep it as fair as possible and found this in less than 5 minutes...

I would not critique your use of this fun benchmark the way I tend to if I did not have evidence to back up my position, including private evals beyond SVGs that I can reliably use to point out major deviations between what a models claimed performance is according to major benchmarks vs the actual performance outside these known test cases.

I will also say that while I have a lot to be critical of regarding Anthropics modus operandi, especially how they present interesting findings like their j-space work, which I found was irresponsibly anthropomorphic in their reporting, especially as this wasn't a first in model interpretability, but mainly a leap due to being applied to a larger model, but of all the labs, they are the ones that never underperform my evals vs public ones and they appear to strictly keep their training data sanitised.

Happy to discuss public vs private evals and the merit of each if you'd like, I do appreciate your reporting in general but just think the SVG benches have become evidently polluted, which is also why even simple queries in my benchmarks are private. Just saw Thinking Machines Inkling model succeed in certain queries that neither Fable 5, nor GPT-5.6 Sol on any reasoning level managed, which I feel is valuable to truly gauge where we are at. Informs my work with models, my views of the industry and my assessment of the future these tools have, along with how to best implement them to enable better UX.

[0] https://simonwillison.net/2025/Sep/20/grok-4-fast/

[1] https://simonwillison.net/2026/Apr/16/qwen-beats-opus/

Kimi K3, and what we can still learn from the pelican benchmark