This doesn't deserve to be downvoted. Above all else, code review is the moment for pair programming. You have the original author personally give you a guided

This doesn't deserve to be downvoted. Above all else, code review is the moment for pair programming. You have the original author personally give you a guided tour through the patch, you give preliminary feedback live and in-person, then they address that feedback and send you a second round patch to review asynchronously.