Digital BW, The Print

Thanks everyone, for your responses to my question. The
depth of expertise on this group is simply amazing to me.

It helps to understand, as Antonis said, that "100% ink
coverage" means is not an absolute amount of ink, but is
determined rather experimentally. I now realize that the 
first step in the QTR calibration procedure, which involves 
printing a special test pattern and choosing at what point 
the ink completely covers a patch of paper, is the 
experiment QTR uses to determine an ink limit for a 
particular printer. 

The practical upshot, if I understand it, is that ink limits
are not adjusted on a print-by-print basis, but rather once
for the ink/printer combination. was my main concern,
though I didn't know it when I asked the question.

If that simplistic accessment is wrong (for inkjet printing)
please feel free to correct/amend; otherwise, I think I 
understand what I need to for the time being.

Again, thanks,
-david