[ahuth]

The point is valid and one I hadn't thought of: would employees be truthful knowing that what they say will be reported to the company?

I like to think that I would, but none of us know how we would react until put in that situation.

[yawboakye]

It depends on the nature of authority and the safety of work environment. GitHub-according-to-the-media promotes exactly that. Not forgetting GitHub's engineers are probably good enough to land another job almost immediately after they quit GitHub.