Defending their thinking?? Does that make their calculations correct because they can defend the way the came to it? It sounds like math for lawyers! (and if it weren't for lawyers, we wouldn't need them....)
I stand by the original writer of this topic. The math program is a nice idea, but it isn't working. Too many parents in my area are pulling their children out of public school simply to get away from the unsatisfactory math program. What good is math if you have to spend time thinking about why it's there? By all means, teach a few lessons of why, but a whole lot more of Do Do Do. People who learn by rote have much better memories - I'd say that's an advantage.