Well, the integra article was interesting, but the final paragraph illustrates his lack of knowledge. At that point he has basically forgotten that you have to treat the entire exhaust as a complete system, and that the exhaust flow is limited by your 'tightest' component. Sure, putting a fire hose on a garden hose does squat, but putting a garden hose on a fire hose _will_ restrict flow.
Honestly, I can't imagine what backpressure does for you beyond increasing your pumping losses. I'd much rather have some properly tuned equal length headers tuned for my cruising speed that properly scavenge exhaust (providing negative backpressure.)
http://www.cobbtuning.com/info/?ID=3222