Originally posted by gatorguy It is a useful metric to know, in portraiture for example, but not the most important attribute of the lens.
I'm writing most reviews for Pentaxforums (and elsewhere), and I agree with this.
That is why we supplement the test charts with real-life samples.
I would say that there is a minimum level of sharpness required, beyond which it's a matter of diminishing returns.
It's not useless (better sharpness makes it easier to crop, and is required when your sensor resolution increases) but not the only thing of importance.
A soft image will be annoying for viewers (except if there is intent) but beyond a certain point, no one is going to look at an image and say "so shaaaarp!". They'll look at other things.
That is also why lens tests cover sharpness, aberrations, bokeh, distortion, vignetting, etc.