This is not exactly a PERFECT example, because of angle, point of view, and zoom level. Nonetheless, I have captured 2 boats, with similar camera angles, and resized the images to show appropriate length. The top boat is 37 feet, the bottom boat is 38 feet. Also, these are both boats with consierable head room, etc.
I think the 37 TOWERS over the 38. and if you had the opportunity as I did to see them side-by-side, you would really see it.
The 37 is slightly taller, but it's mainly about shape.
Take for example, the 90's Camaro, and the 80's Camaro. If you look at the two, in a picture, separately, you would swear that the newer Camaro is smaller. In actuallity, the newer Camaro is taller, longer and wider than the older Camaro.
You can also see this by comparing a 66 Chevelle and a 69 Chevelle. The 69 looks smaller, but it's actually quite a considerable amount bigger.
But that's all appearance. What TeamBajaMarine.com is referring to is the girth, the actual size, not the LOA.
But I see what your saying too. It's hard to believe that a 30 would perform better than a 33. I guess I would have to see it for myself to believe it.