Sulfite is not a panacea for grain or image quality. When used in a developer like D-76 and Xtol, sulfite is very effective in enhancing the image quality (overall enlargability) but this is not true when added to more vigorous developers like Rodinal. In my view addition of sulfite to Rodinal does not increase enlargeability of the negative. However, Rodinal tends to give lower speed, especially with 400-speed and faster films, and addition of 20g/L of sulfite seems to reverse some of the speed loss. Again, if you care about this, I think it's better to use some other developer, like XTOL 1+1, which give full speed and good negative quality.
Regarding the notion that sulfite makes grains mushy or fuzzy. This is not true. If you look at images developed in stock strength D-76, Xtol or DS-10 under a high quality microscope, you'll see a very crisp, sharp grains. I do see the same crisp grains when I enlarge the negative using a point source light and an enlarging lens set at an optimal condition. Some enlarging systems are not capable of this level of resolution and they may render finer grains fuzzy, but this is not because the developer makes grain fuzzy.
As a more drastic example, if you develop any film in D-19, which is a high sulfite developer, you'll get giant and crisp grain. You'll also reailze that D-19 gives no enhancement of accutance and the image doesn't look as sharp as ones you get with D-76.
Actual resolution of the image is not decreased by sulfite at all. What matters more, especially for those who make large prints is to decrease granularity and maintain a good level of accutance at the same time. Of course, adding sulfite to some existing developers is not a very effective solution here.
I also think that developer preferences depend hugely on enlargement factors typically used by the user. For example, I customarily make 10x, 12x, 18x or larger enlargements and developers like DS-10 are almost essential to me. But those who make 8x or smaller enlargements may not find grains a main factor and may prefer something different. Generally, negatives for smaller enlargements require more accutance enhancement to match the overall visual sharpness of the finished prints. We experience this in the digital world as well... you give just good amount of sharpening to the original image and make a smaller version for web presentation, and realize that you need a bit more sharpening. Same thing happens in the enlarger... or in the viewer's visual system, rather.