Well, neither do I to be honest. Powerful is a really loose term and some things - like the impact of better texture filtering and having a flicker filter on everything - are pretty hard to describe simply in terms of "power". If you just compare poly or pixel throughput you can probably be pretty definite about things, but objectively judging the impact of "more colourful textures" for instance seems pretty ... difficult.
I must apologise in advance because it's Controversy Time! Metroid, F-Zero and Resident Evil 4 all looked great IMO. Super Mario Sunshine looked pretty nice too, and Twilight Princess looked even better. The Star Wars Rogue Squadron games on the other hand, didn't.
Bland, barren environments with low poly rigid models moving around doing nothing much in particular. I had 2 or 3 - can't remember - and it looked poor. And the on-foot sections were laughably bad - horrible infact. But there'd always be some PR stuff about amazing lighting and 20 million polygons per second and wham, it's a Factor Five love in as a few un-animated boxes move around above some snow or dirt. Take away the Star Wars and Nintendo fan multipliers and THE EMPEROR IS NAKED GOD DAMN IT!!!
Man, I got so sick of people posting pictures of the trees as the answer to any and every possible criticism of the game's visuals. Yeah, the game looks much better when you can't see anything because of trees.
It's funny how fast the love for Factor 5 disappeared when the Star Wars franchise disappeared and they "betrayed" Nintendo. And dragons are a lot harder to animate than an X-Wing.
He couldn't remember some bullshit theoretical figures (and didn't claim he could) but spent time butting his head against the hardware during actual professional game development. I think that's far more insightful than something off a spec sheet, or even better (worse), a PR claim or something like it given to the none technical gaming press.
I think it's odd the way you dismiss what he says pretty much out of hand - unless I'm underestimating your experience and your CPU poly clipping for the Cube was loads better than his.