Riding slow on a 700 or 800 pound cruiser for a new rider is difficult to master. I've been riding almost 40 years but when I took the course I saw guys who had purchased big bikes and had no idea how to handle them other than going in a straight line. I hadn't owned a bike in a few years and I thought the MSF was a good reminder course.
As far as riding between the cones and only going 17 miles an hour, just exactly how would you teach a course to beginners? Granted one of our instructors was a p**** who thought he was a drill sgt but, all in all, it was a good course if it did nothing but teach new riders that the bike is going where your eyes are pointing. Amazing how many new riders don't know that.
Diss it all you want, more people are riding than ever before and it's more dangerous out there than ever before. What ever can be done to keep people from getting hurt or killed enjoying an enjoyable activity is a good thing.
When I got my America, I went to the high school parking lot and practiced slow riding so I wouldn't drop it the first time I went to the mall and a car pulled out. Being cool is a lot less important to me at my age than being safe.