Interestingly, my benchmark results of GPT 4 Turbo show an opposite result: the new gpt-4-1106-preview did significantly better on the first try than the March and June models.
https://aider.chat/docs/benchmarks-1106.html
Aider benchmarks against the 133 Exercism python exercises, not js exercises that mentat's benchmark uses. So this is not an apples-to-apples comparison, but there doesn't seem to be a strong reason to expect qualitatively different results.
I also notice that the instructions prompt that mentat uses seems to be inspired by the aider benchmark? Glad to see others adopting similar benchmarking approaches.
https://github.com/AbanteAI/mentat/blob/main/tests/benchmark...
https://github.com/paul-gauthier/aider/blob/main/benchmark/p...
Edit: Not sure if the mentat authors are in this thread? After looking around a bit, there seems to be a bunch of aider code in your repo. Some attribution would be appreciated. It might even be required under aider's Apache 2.0 license?