I disagree Westie.
A manager has a responsibility to provide timely, accurate, and documented feedback to an employee, precisely because they have power over that person's continued employment. It sounds like that didn't happen here. New managers do tend to have trouble with negative feedback, especially if they have become close to a report.
One way in which method could do better in the future is to ask for assessments proactively, and ask specifically for ways in which he could improve his performance. That'd be taking responsibility for himself. Another way in which he can improve is to monitor the professionalism of his relationship with his manager so that it does not become intimate to such an extent that it interferes with proper business communication, and it sounds like he's doing so.