In a group people tend to modulate their feelings or get defensive. One on one you can talk to a person and see what's really getting at them. Groups also tend to cause trouble when people really let it rip and end up causing more hurt than existed in the first place. Once you've talked to people one on one and really felt them out, then you might want to bring them together and come to a common conclusion - work on modulating conflict and not dredging dirt. If you're management, do it yourself.
Nothing is easier than delegating inter-worker conflicts off to one of the workers.
If they are bad at it, the problem will stay or get worse. If they are good at it, you've undermined your own credibility. Face the issue and deal with it. Getting peoples feelings out means nothing without follow through. The whole process is meaningless if you're not committed to trying to come to solid conclusions.