This was a recent add to the video plug-ins, and the other day, it saved my butt on a shot where the lens lost focus and went a little soft. We've had sharpening tools before, and generally you can't crank them more than a percent or two before your image looks like a heavy Xerox... but the Noise Reduction plug-in seems to give better results, if you play with the various combinations it offers. I stay with the low to medium settings.
It wasn't necessarily meant to be used this way: its "official" purpose, I guess, is to reduce mosquito noise in small images you had to scale-up. I've also applied it to consumer camcorder footage that's ostensibly 2k but not the same resolution as the broadcast cams.
A trick I've used for soft footage before is to duplicate the layer, put it into monochrome and enhance that, then mix it into the original channel with a blend mode and opacity adjustment to increase *apparent* resolution/sharpness. The Noise Reduction plug-in seems to give a similar look, but with just a couple clicks.
I've done this before with the Neat Video plug-in. Another tip is to limit the sharpening with a mask. For example just on a person's face. For me this helps avoid the "artifacted" look that sharpening adds. If someone's eyes are sharp you tend to think the shot is in focus.
Of course, I've never screwed up focus on anything I've shot...