you make a good point. but i think you also hit the nail on the head when you mentioned both 350's, while missing what the phrase really means, altogether.
the whole message in the "n r f d" quote is in regards to the SAME engine. Not completely different engines.
Sure the porsche engine is almost half as small and makes 1 more horsepower. But what happens when you take the dynamics of the 215ci engine, and make everything bigger? you're allowed to stuff more air, and more fuel, and you then create more energy due to a larger combustible area.
the saying doesnt apply to cross-platform or totally different engine designs due to the fact that certain engines have different heads that would allow better combustion chamber design, therefore increasing possible compression ratios. i.e. - a replacement for displacement. this is apples to oranges.
now, apples to apples, you'd have the same engine, only stroked, or bored out, and with the same compression, everything updated to provide for the new parameters, and you'd make more power if your calculations are correct.
a honda head flows much more than a nissan head. just look at the b16 or b18 head, and compare to an RB25 head, by not counting 2 cylinders. So if you make it bigger, it doesn't mean you're creating as much energy.
you can read about the immense flow ratings of a stock honda head on endyn's website. i'd like to replace the "n r f d" quote with "the more you can ram, the more it can WHAM!" but that sounds a little...