Pretty classic exchange, I hope Marcel never comes back. I read his ebook. I have also spent time with aimpoint, I have the digital level, the charts and I putt on my intended line. Marcel's system is better, faster and creates a more true and deeper knowledge of the subject. I am not as good a golfer as you iacas, but I took the time to read and understand his system, you bang on about parabolas being irrelevant but you fail to understand that it is sections on a parabola not the entire parabola that describe a balls behavior. To you other readers out there, you can learn a lot from both systems, they are pretty similar actually, but aimpoint is very dependent on advance knowledge of stimp, percentages of slope and the charts information. Marcel's is more creative.
Iacas... You never know what will make you a better player, I am sure that at some point you did not use aim point, but you are a better player now that you use them. Currently you do not understand how certain sections of a parabola can illustrate perfectly the putt you are facing. If you had the knowledge you would be an even better player. Forums can expose you to new ideas if you let them or as in this particular case they can be like a high school clique.