That is paramount to saying: 3" is the only system you should ever use on a big block. Too broad, too blanket and just doesn't take into consideration so many variables.
You're money on with everything else, but to simply say one size fits all is blasphemy.
And like I said, it depends on the end users use of the car. Perhaps, just maybe, a quiter ride is what he wants in the long run for long hauls? Perhaps, he doesn't care and wants every last pony available? As posted, the video is an interesting video. Like I said, to a degree, I agree.