Humor

i think humor is a key part to a lot of healthy group and team communication.  First, it starts off as a great ice breaker.  it allows the group members to feel more at ease and comfortable, instead of feeling like you're dealing with a hard-ass.  Second, at times there may be tension that might going on within a group, so laughing off something could be an alternative to taking the serious route.  Lastly, humor is great because it's a good tool to use to help get messages across sometimes.

on the other hand, humor can be a device that distracts the group.  there might be times when you have those class clowns or those comedians who try to make everything into a joke.  the problem with that is that people may view that person as obnoxious and someone who is cooperating with the group.  I'm pretty sure we have had those people in our groups throughout our life time that just try to be overly funny, and instead of being an asset to the group, they become just an ass.  I think it is important to have a balance of humor and seriousness.  It helps people calm down and sometimes we may look for that person to kind of set the mood or tone with the group when times are rough with the group.