Readers looking for thrills rarely turn to official reports written by groups of worthies. At first glance, one from a body soporifically named the UN High-Level Expert Group on the Net-Zero Emissions Commitments of Non-State Entities might be expected to cure insomnia. The team of experts, led by Catherine McKenna, a former Canadian minister, has spent the past seven months poring over the proliferating climate commitments of banks and big…