Powa and powa curve can be altered by components I stated. Canada so ur answer is because u can have a variable ext timing. There's at least an answer to why it's good if it works. That's the other deal if it works, for how long it works, and how much it impacts powa. Zilla had an answer that applies but does it work? I've been on a PV or two and like to see why peeps like PV