Depends what you mean by this. I'd recommend reading some of Massad Ayoobs books. He shows some cases where a cocked revolver caused an AD that could have been deemed manslaughter, whereas if it was an intentional shot it would have been justified.
A cocked revolver would not go off if the shooter did not have his finger inside the trigger guard when he was not ready to shoot. It was not an AD it was a NEGLIGENT discharge.
Lightening the trigger to increase accuracy to hit the intended target is fine. Because the intended victim should be able to show that he is proficient, through training, with the firearm at the trigger weight he/she selected.