[solipsism]

I'm curious what you mean by grab a lock and schedule and wait for a code review. I've used all sorts of different SCMs, code review software, in-person code review processes, etc.. but I've never heard of anything like that. Could you describe your process to us in more detail?

[zelos]

I haven't done it myself, but I know of teams that use a lock for integrating changes to the main branch.

Without it the rate of change in the branch was fast enough that submissions would be preempted by someone else's and you'd have to rerun presubmission tests etc.