Mike,
I have used the XCMYK concept many times in the past 35-odd years with AM screening, and of course it works. The only problem is that pastel tones tend to become less saturated than at regular GRACoL/ISO 12647-2 densities, due to the mass tone effect caused by thicker ink films on the halftone dots.
Once I started combining higher densities with FM, the mass tone problem was eliminated because the tiny FM island dots just cannot hold a thicker ink film. In fact pastels actually become cleaner.
Bottom line: XCMYK with AM may work for images containing mostly dark, rich colors, but is probably not a good idea when you want clean, saturated pastel colors, especially pinks and light blues.
Your results, of course, may differ.
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Don Hutcheson
HutchColor, LLC
Washington, NJ USA
don@...M: 908-500-0341
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