Contrast control of negatives usually proceeds via unsharp positive masking. The techniques are supremely exacting and precise. Special equipment such as masking film and precision register punches and pins is part of the deal. Those who excell at this have generally done an extended apprenticeship. Again, there is a lot of deep knowledge here.
Is wilful study required?
Excellent answers, BTW.
I do use a digital device in my photographic pursuits when necessary.
When someone rags on me for using film, I use a middle digit, upraised.