Espressivo, qleg, sostenuto, normale and the rules

Does anyone know what expression level does in the expressionlist.tpk? I'm asking because I noticed while reworking my rules that normale doesn't have an end techniques line, and it still turns off espressivo and sostenuto. Does it have anything to do with that, or is it hard-coded behavior? I'm reluctant to change anything as long as I don't understand how it works.
Also, has the parser changed? I mean in the previous build if a rule was after another in the rules file, it would overwrite it if the conditions were met, but now I see in 3oboes that the simple slur rule is after the exp-leg rule, still the exp-leg triggers and the simple slur does not overwrite it. So how does it work now, only one keyswitch/instrument? And would that apply to external midi as well? Or is it something else?
Also, has the parser changed? I mean in the previous build if a rule was after another in the rules file, it would overwrite it if the conditions were met, but now I see in 3oboes that the simple slur rule is after the exp-leg rule, still the exp-leg triggers and the simple slur does not overwrite it. So how does it work now, only one keyswitch/instrument? And would that apply to external midi as well? Or is it something else?