I know a bit more about the beginning of the PP and its the reason I gave at first. Heavyweights don,t need L4 because they are strong enough. Which is simply wrong. You can never be too strong, too fit or technically too skilled.
The pp is fine for two rounds orso, for beginners 3 or 4 because they don,t known how to pace stuff, after that you run into a wall. You simply reach a plateau and need a change. If you are more mature as a rower its not suited in my very humble (yeah right

For you guys, all roughly beginners, its fine. It will teach you guys what you are good for. Enjoy