That is way I said not constraint by your skeleton - or what ever else. The point is that at least some dimensions are obviously correlated, not that all dimensions have to be correlated.
>weight gain in adulthood doesn't cause you to get taller //
Not even a tiny bit, like because of fat feet or more fat on the head? Not trying to be facetious, just seems huge people have fat feet and that there's likely to be a little fat on the bottom of the foot. Mind you that's going to be countered by compression of the spine, so there could be a inverse correlation?