05-04-07 Ray Moxom has kindly submitted the following suggestion of steps you can take prior to the resizing process:

I like to convert the image to Lab Colour before sharpening - I then use channels where I sharpen the "Lightness" Channel before converting back to RGB. My starting Unsharp Mask settings are Amount=100, Radius=1, Threshold=3. I find that this Lab Colour sharpening method allows some nice sharpening with less risk of artefacts.