Curious the reason that a grader would wind up preferring this. Honest mistake in the grading criteria? Or some spillover from criteria designed to cause underperformance in, say, competitor model creation? It was not very long ago[1] that Anthropic announced and then walked back their strategy on this. Would not surprise me if OpenAI has been doing it silently all along.
[1]: https://mlq.ai/news/anthropic-reverses-secret-policy-that-si...