Bad Guys Always Die question (huge flaw in logic)

[Mr. Porter]

When Dre says that he only took 8 paces instead of 10, what's his advantage really? Instead of them being a total of 20 paces away from each other, they will be 18. All because Dre took 2 less paces, it doesn't put him at any sort of advantage. Am I right?

[K Reidy]

Once you hit ten paces is when you turn around and shoot, so by taking 8 he could turn around and shoot just before the other person can turn and shoot

[Atone]

it just means dre would shoot first