The paper isn't proposing "monitor chain of thought for safety" - that's already standard practice. The core finding is that training on CoT monitors destroys them. They provide empirical evidence that doing the obvious thing - training models not to have "bad thoughts" - causes them to learn obfuscated reward hacking instead.
The paper demonstrates that current models are already performing complex reward hacks in production environments, and that attempts to fix this via CoT training make the problem worse, not better.
As for your "40 authors" snark - this is a position paper where researchers from competing labs (OpenAI, Anthropic, DeepMind, government safety institutes) are jointly committing to NOT do something that's locally tempting but globally catastrophic. Getting industry consensus on "don't train away bad thoughts even though it would make your models look safer" is the opposite of trivial.
This reads like someone who saw a medical consensus statement saying "this common treatment kills patients" and responded with "did one person discover medicine exists and everyone else just agreed?"