I believe it was here that I once ran across a chart of bra sizes and the progressing volumes of each cup and I kind of remember that by the larger cup sizes on the chart, the volume had already hit like 1000cc just to advance another size. When you think about it logically, knowing it takes 8x the volume to double the size of any object, each ½" of expansion, always surrounding the previous ½", would always require more. While this works fine for big spherical fake breasts where the cup covers a specific portion of the breast (but we already know such cups really don't contain enough breast to actually give support as the bands are always so large that half the unberboob is uncovered), it would be entirely different for huge naturals that require the support, hence need a proper fitting band and a lot more flesh in the cups. Of course, when we are talking about cup sizes like Q or R, the girl with a 32" underbust has already exceeded what is offered, so she has to buy larger bands that cannot give the needed support. I always think of BustyyyJenny with this respect; because of the massive size of her incredibly firm tubular breasts (perhaps 9-10" in diameter and at least 17" in length), she was using a 48R just to cover her enormous areola, yet with a 32" underbust, it offered no support and probably contained less than 10% of her 94 pounds of breasts. I remember Llewyn & I crunching some numbers on her thread a couple months ago on shapes and volumes (Jenny being over 42,000cc) and without intending to do so, essentially confirmed that Beshine has to be over 80 pounds herself. I guess that explains her frequent need to rest when walking.