I think it's fine under a few circumstances. First, it shouldn't be the only way to discipline a child or your only option. Really it should be the last if the kid just will not listen to reason. Also, using things like rulers and cables from the back of the tv (oh the memories) shouldn't be use. A simply smack in the wrist, hand or buttcheek is more than enough to tell the kid "cut that shit out now." A decent and proper scolding should never leave a mark.
Either way, if you hit your children, but your a bad parent to begin with, then your just beating them. Like drink in front of them, smoke in front of them, curse like a sailor, teaching them obvious bad habits even if you don't mean to. Kids pick up on everything you do and once they get to a certain age they will understand that they were hit because they were doing something bad and sometimes words will not suffice.
Just as a quick thing, my parents smack me from to time. Sometimes with their own hand or like a sandal or ruler and while I don't think it was proper parenting to hit me with those "tools", I understood why they did it and I turn out to be a kind person, thanks to them being strict and disciplining me, by both vocal lectures/scoldings or light, physical strikes, I turn out to be a decent person. Also, I have always looked up to them as good parents. I never remember being angry at them for more than a few hours.
To wrap up, it's fine and perfectly natural to discipline children with light scoldings, not to hurt, but to teach (if that makes sense.) You aren't scarring them for life if there is a good reason behind said action and in time, they should understand and reflect on the reasons why they were scolded.
PS: I did not read the article, just answered based on the title.