QTR-Quadtone RIP

I have a B&W (and negatives) oriented question.
I wonder what really goes on when you change the ink limit in a QTR profile.
Let's say you lower the default ink limit from 10 to 5.
Looking at the curves in QTR-Curveview tells the effect is like applying a "0;0 100;50" general curve in the profile.
Is it what is really happening?
Then what happens with the digital information of the file that is sent to the printer, is there some loss, or only less ink droplets with the same unaltered file?
With a lower ink limit, less ink is dropped onto paper, does that mean less analog information? Does that mean less DPI ?!
I'm a bit confused about the overall density reduction (eventually compensated by a different ink set) and the capability of the printer to produce the tonal differences of the original file.
Maybe the human vision's limit is a key factor here, but would a reasonable low ink limit exist?


Thanks for your help.


Stefan Christiansen