Thank you Mr. Roberts for posting the pieced from the CATO Institute.
The SYG laws are widely misunderstood it seems. The misunderstanding covers both detractors and supporters of the laws. Even the name is misleading as those involved still have an obligation to "retreat", withdraw or avoid the confrontation. If the confrontation develops into a physical one they still have an obligation to seek to end it short of death.
The defensive concept of shooting to stop aggression rather than shooting to kill still applies.
If your actions provoke an encounter the law may not see self defense no matter who threw the first punch.