Chuck,

The issue is that it is almost "glued" shut but once you break your thumb and force it to start opening it functions normally for the rest of the hairspring's travel. Thus, I don't think the problem is the hardness/resistance of the toplever spring, but rather something else is amiss?

Does that help dial in why the first part of the travel (arguably it should be the easiest part) is the hardest to get started?