I very seriously disagree with your statement that this could have changed the outcome in the Ersland case. That case involved two very separate and distinct incidents.
1) The kids came in to rob the store. Ersland pulled a gun and shot one, the other ran away.
2) Ersland used deadly force to kill a robber after the threat had been neutralized.
There are too many factors in evidence that make this go way beyond a legit SD shooting. He stepped over the robber, turned his back to him, and got another gun. Then he calmly unloaded 2nd gun into the robber, who wasn't moving.
Then he lied to the cops about a whole manner of things. He should have kept his big yap shut.
While I find the sentence to be a bit harsh, I find the verdict to be spot on. There are a TON of people who disagree with me, and I think their opinions are based on emotion or ignorance of the SD laws.
Having said that, I like the new law. I run a business, and open carry inside my business. I will defend myself and my employees if forced to. I will not execute a criminal because I'm sick and tired of being robbed. Iwill only defend myself to the point that the threat to my/our lives is neutralized or removed from the equation.