Could the 40mm F1.4 Art be One of the Sharpest Sigma Lenses Ever Made?

There's no doubt about the fact that Sigma lenses are some of the sharpest currently available. From the 18-35mm f1.8 Art that shook the world of APS-C cameras a few years back, to the super sharp 135mm f1.8 Art that was released last year; sharpness hasn't ever really been an issue with Art series lenses. Just how much sharper can their lenses possibly get though? Quite a bit it seems. Kai Wong recently took this massive prime lens out onto the streets of London during a Santa festival to see h...