Google's estimation for my country is always less than what is achievable if you stick to the speed limit. I guess they calculate it based on other drivers.
My team uses task number and title as a commit message. We just can't fit all the description from task into one line of comment. So, when we look at git blame - we get a reference to a task in project management tool where we can find all the reasons behind a given change.
If there are more commits for the same task, all of them bare the same commit message. After each review, we add a comment to project management tool. That way we focus only on newer commits when performing another round of reviews.
Every other attempt to describe changes and intentions in one line seems doomed to me.