Your response suggests that you consider a smacking a poor first choice of discipline. I've been watching how my brother and sister-in-law raise my niece (she's 2 and a bit). They smack, but it is never the first choice of discipline. In fact, it doesn't happen much at all. I've also always seen it only after Paige knows she is being disobedient. That said, my brother and his wife love their daughter very much and she knows it. Smacks are always clearly directed in response to a particular action by her.
Wade.