I've been reading the court minutes available online and found the one discussing aggravating factors for the death penalty. Basically is says in it that the opinion at that time was that TA was shot then stabbed and since it took all those stab wounds to "achieve her criminal goal" of killing TA the killing wasn't especially "heinous or depraved". This might explain the shot last theory rather than the shot first since I think there are valid arguments on both sides of this issue.
http://www.courtminutes.maricopa.gov/docs/Criminal/082009/m3846408.pdf
http://www.courtminutes.maricopa.gov/docs/Criminal/082009/m3846408.pdf