<p>I have also noticed that on pictures viewed on monitor visually similar unsharp mask sharpening results can be obtained with larger radius plus smaller amount and smaller radius plus higher amount.<br>
Different programs have different methods of defining unsharp mask sharpening. But the idea is same - radius, amount and threshold.<br>
Usually with digital images I use contrast usm - very high radius, low amount, no threshold plus detail sharpening usm - low radius, high amount, threshold 2. Sometimes detail sharpening usm is masked and applied only to partial picture.<br>
The sharpening methods You mention are somewhat more advanced, and probably optimized for inkjet printing, but perhaps they work in similar fashion what comes to radius amount relation.<br>
I am rather new in inkjet printing, but I have not yet noticed need for additional sharpening specially for inkjet prints. I have turned off almoust all printer driver included enhancements. If You have 300dpi or 600dpi source of sharp shot image, glossy or semi-glossy paper, then You are likely to recieve nice detailed print.</p>