The fit might be a little less than perfect, but it is close enough for me. My version of the Diminishing Ribs cardigan was knit in (mostly) the recommended yarn, Tahki Savoy. The result is ultra soft, smooth and slinky-drapey.
Three changes perfected the fit: (1) lowering the front neckline by short-rowing the back after the ribbing; (2) increasing twice as often as recommended for the lower portion of the raglan line, thereby reducing the number of stitches cast on under the arms and rounding out the bottom of the armsyce; (3) decreasing down to the waist, using the stitch counts for a size smaller below the waist. The ribbing begins an inch lower, falling at my natural waist.
The end result is quite comfortable and easy to wear. The only reason there's a bit of excess fabric by my shoulders in this back shot is that my arms are pulled back. I've put more photos and details in my Ravelry project page, including one with my arms down.
There I explain my struggle with the sleeves. For here, I'll just say that this was the most satisfactory sleeve I could manage with the yarn I had left. With about the right quantity of yarn, (6 balls of Tahki Savoy and 2 of Louisa Harding Grace), I was lucky to get a cardigan that is a size larger in the shoulders and 2 inches longer than recommended, with sleeves 4 inches longer than recommended. The sleeves sit nicely and don't bunch or flare when I move my arms. After multiple rips and reknits, they are good enough.
Although the sleeves were a struggle, modifying the body was simple. I benefitted from the hundreds of projects on Ravelry, a wonderful resource of useful notes and suggestions. It was those other projects that convinced me it was important to get the fit right for this cardigan. Without buttons, it is the fit that keeps it in place, even when I stand more casually.
There's enough ease at the neckline to allow it to be pinned closed, but a closure isn't really needed. I'm prone to throw on my cardigans and often don't bother to button them, even when it is cold out.
Which is what it has been out--cold. The angel has left for the winter, hiding behind her blankets of snow. She'll be back in the spring.