I think we are saying the same thing. Let me put it this way:
If going into the final series the Brewers are ahead by 2 games or 3 games, the Cubs would have to sweep the series to take the division.
If going into the final series the Brewers are ahead by one game, the teams are tied, or the Cubs are ahead by one game, the winner of the series will win the division.
If going into the series the Cubs lead by 2 or 3 games, the Brewers would have to sweep the series to win the division.
That’s why I set a 4 game lead going into that series.
Being ahead by 3 games going into series is basically the same as being ahead by 2 games.
Being ahead or behind by 1 game going into the series are both basically the same as being tied.
But clearly, being ahead by 2 or 3 games would be better than being ahead by 1 game.