GitLab team member here for over 3 years. Can confirm, it works exactly as advertised. The detailed description above is totally in line with my experience.
We recently codified the operating model in a course we're calling TeamOps. It's a first iteration, but anyone is welcome to take the course and provide feedback. https://about.gitlab.com/teamops/
The two essential elements of why this works.
1. Communication (both formal — work related — and informal) is explicitly defined. https://about.gitlab.com/handbook/communication/
2. There's absolute executive sponsorship to work "handbook-first." If it's not in the handbook, it's as if it doesn't exist. The top-down belief in the system enables it to function. https://about.gitlab.com/company/culture/all-remote/handbook...
We recently codified the operating model in a course we're calling TeamOps. It's a first iteration, but anyone is welcome to take the course and provide feedback. https://about.gitlab.com/teamops/