Amazing clever stuff Mike, great  
I took some macro shots this afternoon and I tried it on one image of a pink flower with a red beetle on it against a mainly green background of grass stalks. I first sharpened excluding the green and a defintie difference could be seen for the normal USM, the background remained as shot and relatively soft.
I then saved that filtered image (CR2) to a tiff and then selected the green background again but then softened it (negative %). That really made a difference.
Would it be possible to do a 2-stage process like that all at once? Something for the future perhaps.
I can see a great deal of use for this feature, no doubt some practice will be required.
Here are the links to the images:

EDIT: I've now deleted these images as v107 made further improvements to TTS

Terry