Ron stated it better then I did .
Now some will disagree but you do IMO actually marginally lighten the pull of the trigger as well as reduce travel do to the engagement notch in the front trigger becoming more and more angled as you screw in the adjustment .
Also it should be noted that not all double set triggers fire the lock while unset and using the front trigger . They however for the most part adjust the same and the adjustment does the same thing .

I have seen 3 different trigger sets on Traditional CVA rifles .
a) standard pivot/ leverage type trigger
b) double set hunting trigger which will fire the lock both set and unset
c) double set target trigger which will only fire the lock when set IE it acts more as a single set . It should be noted that this trigger is capable of being set up as a true double set . But it requires re inletting the triggers . In at least 2 cases it also required a new sear

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