The author of that post is pro-spanking and embraces the "children need to be trained to be good" mindset. No offens intended to Courtney at all
You could do a search on her blog and get an idea of her views.
A good book, oddly missing, is the OTHER Clarkson book (Heartfelt Discipline) that Clay wrote. He's rewriting/editing it and it's supposed to be released again soon (fall?) But I'm sure she would not agree with his conclusions.
The Clarkson books and the Five Love Lanugages are the only GBD on that list, I believe.