Peter back before digital the photo magazines would run comparative tests of film/developer combinations, and show enlarged sections from images to illustrate the grain, sharpness (definition) etc.

So you could have a sharp looking image made with a developer like Acutol X which had great initial impact because of the high acutance but lacking very fine detail because of increased grain size, another developer might give excellent fine grain at the expense of slight apparent sharpness (Microdol-X/PerceptoL0 while a third gave a better overall balance of fine grain, sharpness rendering of fine detal, Xtol would fall into this category.