Thanks for all the thoughtful responses everyone. I'll be spending the rest of today reading before I get some practice. Murray thanks for the link, that looks really interesting and I can clearly see how this technique can be very demanding. I hope to be able to tackle it as well one day.
One thing that I think important is that digital and analog are different, and it may not be entirely possible to duplicate what you can do with either using the other.
Also, prior to doing any of the suggested means of modifying regions of the curve, it is very important to get the best straight print you can as a place to start. I print with white and black patches, which helps me avoid the machinations of my brain when it tries to convince me that everything is just fine, that the darkest tone I see is really black, that the lightest tone is really white. Our brains work well in comparing but are not very good with determining absolutes without a standard for comparison.
The digital grayscale is quite unlike the photographic grayscale. I do the kind of thing you do when I convert from one to the other, because that linear equal step scale that you get naturally with the digital just doesn't look right to me. I want the steps to be unequal, as they are in the traditional silver medium. I suspect that what you are trying to do may well be what you would get anyway without doing much to change anything. Just a hunch, but if it were me, I know that would be true.
I work with students a lot. It is often hard to convince them that most of the problems they see in a print would disappear if they simply made a straight print. The tendency is to try all manor of complicated things without ever doing the simple ones.
We humans are very strange creatures.