Should We Encourage Competition (in kids)?

I know that not all readers on this blog are parents, but anyone interested in economics is, by definition, interested in competition. I don't know how many times I've let my son beat me in some game or another. He's getting better at hockey, so the games we play in our shoes in the garage are getting more competitive (I just hope that he'll remember all of these times when he's a squirt and skating circles around me). Check out this article about the role of competition in raising kids in the New York Times this weekend. Aside from the fact that I know the dude in the picture, it is a great article about teaching competition, cooperation and a mix of both. So, he still didn't answer my question -- is it okay to be like Phil Dunphy in Modern Family when he slammed Luke in trampoline basketball?