I think weight plays a bigger role than height. Case in point:
I actually have a Contact 4x4 in 178 length. Heavy, stiff, fast ski. I'm 6'2" and was formerly 220 lbs. I could flex the skis no problem and hit fast speeds. Too stiff in the bumps but rockets on groomers. Then I lost 30 lbs. I'm still the same height but only 190 lbs. Still exact same ski length. And now the 4x4s feel too almost too stiff for me because that extra 30 lbs I was carrying before----coupled WITH its extra force being applied at speed-----made a huge difference. But I'm also stronger now, more "athletic" and can push the 4x4s harder now than when I was a fatass before LOL. I'm stronger, BUT not strong enough to overcome the huge difference in force (more precisely, the lack thereof) being applied to bend the skis since I'm lighter.
Now, as for the height vs length........I do have a short 165 carver at home, but they're softer than the 4x4s though. I highly suspect if I rode the Contact 4x4s in a 165 that I could handle them much easier than the 178. But I don't consider these SL skis, they're more GS type skis. And I would hate the 4x4 in a 165......not for my height (I own 165 skis), not even for my weight (220 lbs or 190 lbs)......but because of the combination of a short stiff skis that wouldn't be compliant as a SL type ski.
Therefore, my height is less of a factor than my weight......which, compared against the length, makes far more difference.
I don't think anyone said height was the only factor. It was just being disputed that weight is the only factor, because that is what was said (ie, the old saw that the ski doesn't know how tall you are, just how heavy you are).
My brother skis the 178 4x4 at 6' 165 and loves it.... I spent a few years skiing 160something skis because that was what my weight said (and everyone said theskionlyknowshowheavyyouare), and then I found some 177s on sale and I've never looked back. Totally the sweet spot for me for skis, unless heavily rockered (then I need to go up), or super duper stiff (then 172ish is great). So for me, height is more important, and I adjust according to stiffness.
I like evo's chart. It seems to me a lot of the manufacturers have been trending toward considering height more than they used to.
And sorry for the tangent.
Seg, I agree with you on all this, including the Evo page. but want to point out a couple things here that aren't really about the height / weight thing, but about the lengths that really make people happy in practice (vs. in their minds).
Point One is that you ski better and more aggressively than all but a tiny handful of women (and men), so the fact that you like to be on a 177 does not mean that the recommendations coming out of a ski mfr's "ski selection wizard" are generally wrong, even if they're wrong for you
Point two is that your habitual terrain matters a ton. On top of ability and energy and ambition, you ski more or less exclusively out west, and more or less exclusively off piste, right? There are lots and lots and lots of skiers in the country and on this board who seldom or never do either of these things. so that can factor in heavily too. Case in point: When we were in Snowbird last month I was on a 174cm full camber ski - big ski for me - and was happy as a clam in the soft, round bumps there, as well as in the lightweight crud and what have you. In the firmer, choppier bumps at Sugarloaf this weekend, though, I was a bit out of my depth on those same boards.
This all reminds me of the feature I keep asking the Powers That Be to institute, namely the "Animal" badge. You know how we have the Ambassador badge and the Instructor badge and the Staff badge. Well, we need an Animal badge for people like iriponsnow and Josh (and you). The purpose of the Animal badge is to alert the casual reader that information provided by the poster needs to be filtered through the lens of knowing that the reader is almost certainly not at the level of strength, ability, and speed of the poster, and should process the information provided accordingly.