I think it's ambiguous because tic-tac-toe is a solved problem, so presumably it's being done as an exercise to learn something about neural nets. If the idea

I think it's ambiguous because tic-tac-toe is a solved problem, so presumably it's being done as an exercise to learn something about neural nets. If the idea were to write an AI to win at a harder game, it would make more sense to add whatever biases you can. You might get better performance that way. Or maybe that's what they thought back when that story was written? Game AI was nothing like we think about it now.