After having spent some time watching the supdem.ex4 with the strategy tester on small TF's I think I understand how it works. Basically as soon as a new extreme is formed on a bar close (top or bottom) the old level is deleted and a new one starts to draw, until a new extreme is formed, starting a new cycle. So, it's less intelligent than what it might look like at a first glance, and then a bit dangerous to be traded on its own. But we knew that already, didn't we? I don't know how the II_SupDem.mq4 works though as I see different levels and don't have time at the moment to check it with the same procedure. Just wanted to bring this to the general attention for people who might be using it. ;)