I find that by very careful placement of the first zone placer to the right on the x-axis of the dialogue box, and then iterating between adjusting it as well as the Highlights and Lights sliders themselves, one can achieve quite subtle control of what happens to real highlights, versus "Lights". As I'm sure you've discovered already, one really should play with those zonal markers to make the most of that tool. By the way, you don't give up a thing in the shadows by playing with the Lights and the Highlights, especially if watching the placement of the zone marker between Darks and Shadows.
I've played with it a bit, but admit I am not even close to proficient... Explain to me how I would increase contrast in the highlights while keeping the maximum brightness at 97% (roughly 248) and at the same time not affecting any pixels below say 87% (roughly 222) using the parametric controls.
Assume at the same time I want to add an inverse adjustment (lower contrast but maintain certain border values) in the shadows.
Finally, suppose once the above are done, I might want to boost contrast slightly throughout the middle range from say 25% through 75%, and increase brightness slightly, but of course without significantly altering either of the earlier adjustments.
I'm sure it can be done and moreover understand a "similar" more general effect could be achieved, but I cannot see how to do it with precision using the slider interface. Yet in curves it is accomplished pretty easily with good precision.