[htobc]

That's pretty much how Google does dev, though not everyone there is consistent about small CLs or the <24 hour SLO for code review.

But yeah, if the team lead is aware of what everyone is working on, and prioritizes fast CLs review, huge amounts of friction and slowdown are removed from the process

[dhosek]

What I’ve seen is things like I ask a question about a piece of code during a PR, the author changes that code and my question vanishes into the ether with no indication (unless it’s lost in the noise of email notifications) that the code was changed and my question is no longer relevant (and if there was, perhaps an answer, the answer is also lost).

[steveklabnik]

Yes. This specific aspect of GitHub is the reason why many teams don't want you to modify commits, but instead, add more commits. Which then also leads to squash-merging branches.

Other systems, like Gerrit, handle this much better!