The sign of peace is to kept in the same place at Mass, says the Congregation for Divine Worship, reports Deacon Greg Chandra, writing about it here, and probably many others. Reporting on this decision, the Italian journalist Sandro Magister mentions Benedict’s remark in his apostolic exhortation Sacramentum Caritatis:
During the synod of bishops was the appropriateness of greater restraint in this gesture, which can be exaggerated and cause a certain distraction in the assembly just before communion. It is important to remember that nothing is lost when the sign sobriety needed to maintain a climate suitable for celebration, for example by making sure to limit the exchange of peace to those who are closest.
As every Catholic knows, in many parishes the peace goes on and on as people, and sometimes priest, move about greeting other people and in some places even having brief conversations, which brings the dramatic movement of the Mass to a crashing halt. I assume the act is thought to be an expression of our community, our fellowship in Christ, etc., but even so it expresses that reality just as well when enacted with the sobriety Benedict mentions and without interrupting too much the forward movement of the Mass. One can only avoid interrupting that movement by what extrovert Americans will think extreme sobriety.
As a symbol, it works best, I think, when limited to those within arm’s reach, which is what “those who are closest” probably means. You’re stuck there with only the people you can reach, which leaves out your friends a couple rows down and at the other end of the pew. You may be with family or friends but everyone else you can reach may be friends but they may also be strangers or people you don’t like or who don’t like you. Standing in front of you may be a couple who’ve annoyed you for the last forty minutes by whispering back and forth about their lunch plans. Standing behind you may be the person you think of as your own personal Nero.
Whoever’s there, to them you say “The peace of the Lord be with you.” You’re supposed to try to mean it, even when speaking to Nero and that annoying inconsiderate couple. That’s something deeper than community and fellowship as we tend to define them, as the elevation or intensifying of natural relationships. It expresses the breaking of natural enmities through Christ and the creation of a community and fellowship marked by its transformation of natural relationships, the good ones as well as the bad.
This seems to me, though I’m not sure I could prove it, much more effectively expressed through the extremely sober exchange of the peace, which has the great benefit of maintaining the forward movement of the Mass.