Double blind is a farce in practice in most CS specialties (maybe not bloated fields like AI/HCI/graphics?). Once you get to the top tier, everyone knows everyone, including the industrial labs, including what they're working on. Most good work is too differentiated to anonymize to well-versed readers: less Neural Networks for X, more Sub-Theory of a Sub-Theory or Version 2 of This Weird Thing.

This may not be obvious to the normal grad student, but after a decade in a community of 1K-10K people, most of them working in groups, it becomes clear. The end result is that the last several top-tier conferences I reviewed for, I basically guessed the authors of all the papers I reviewed, and knew at least one of them personally on each paper. All of that, despite being a "young" member of the community.