No, i think I got it right. He won't feel the power gains (if there are any) if he does things incrementally, so what's the point?
Think about how much it costs to do it all piecemeal too. It's much cheaper to drop the car off and say, "hey, yank the exhaust and put on this new one" than it is to go back and have them put the car on a lift a bunch of times once you realize you need a new muffler, new main cat, new headers, etc. Also, what if someone convinced him to retune his ECU each time to take advantage of the new mods? The bang-for-the-buck is just not there, especially at Porsche prices!
I'm saying that he'd need to do the whole kit and kaboodle to feel anything, for his car to make him go, "Wow! That's so much better!" If he's not going to do that, there's no point. Go for the gold, or go home.
