I know what you mean, but let me explain.
If you define the local name as nil in MissionSetup, you can then define it differently in separate functions without worrying about potential conflicts or glitches. It's the cleanest way.
As for PedAttack, I was just saying that 0-3 has an effect on their fight behavior (keep attacking until the ped is knocked out, or whether they can be distracted by another ped, etc.).