So, the problem for me is, and correct me if this is the wrong approach, it's two completely different techniques.
With the Glock, it's holding the sights on target, while applying about 5 lbs. of pressure on a trigger that's not moving to break, well, not a glass rod, but more like, say, a pretzel.
With the SD, you are trying to hold the sights on target while applying about 8 lbs. of force, and moving the trigger in a good half inch arc. Instead of pressing against a breaking point you've got to try to smoothly move the trigger through pretty much until it stops at the back of the trigger guard without moving the sights. There's no crisp break. What there is of one is more like if you found an old carrot in the back of your fridge.
With the Glock, it's holding the sights on target, while applying about 5 lbs. of pressure on a trigger that's not moving to break, well, not a glass rod, but more like, say, a pretzel.
With the SD, you are trying to hold the sights on target while applying about 8 lbs. of force, and moving the trigger in a good half inch arc. Instead of pressing against a breaking point you've got to try to smoothly move the trigger through pretty much until it stops at the back of the trigger guard without moving the sights. There's no crisp break. What there is of one is more like if you found an old carrot in the back of your fridge.