That's for an earlier system (which also used less compute). AlphaGo was followed by AlphaGo Zero (which is the topic of this article) which did not use the pr

That's for an earlier system (which also used less compute). AlphaGo was followed by AlphaGo Zero (which is the topic of this article) which did not use the process that you describe, it used only the rules of the game and the winning condition.