User blog comment:RePeat/Community Poll on Message Walls/@comment-18933973-20130624000420/@comment-4845243-20130624020710

It would be highly unlikely for someone to need to retire so quickly as to not be able to contact their best friend on chat. This minimizes the number of times users would need to do this.

Also, if privacy is so important, and chat is impossible, then no, it's not really an inconvenience; it would be a relief to contact your friend in private. A situation like this, however, is very unlikely to happen. And as I said, the 0-5 times it may happen do not merit the replacement of message walls.