Parkour Teams? Yes or no?

Some say yes some say no. What do you think? Put your answers in a comment below. make sure to put why you think yes or why you think no.
Key facts
---------------------------------
Bad things
Parkour teams mean competition that could turn ugly.
You can only learn so much by yourself.
Members within the group might "knock" heads.
Good things
You learn a lot more things in a group.
It's good to work with people. (builds social skills)
Power in numbers?