Originally Posted by Tom Duffy
In the epilogue (p. 46) where Dubovoy pays more specific attention to comparison of lens quality between the Canon L and Leica R lenses on the same Canon (digital) body, the author takes into account "sharpness", lens abberations, lens distortion, contrast, color saturation, color accuracy, bokeh, and what he calls an "appealing look" that includes a "brilliant, clean" "three dimensionality". So he's going on more than just resolution. He even numbers his points of comparison in the text, at seven.
He did, however, leave out "a certain je ne sais quoi".