If you didn't know it already, Cubs manager Lou Piniella is here to remind you that the three best records in the National League are in the Central Division. What he doesn't mention as loudly is that no team in the NL has a fatter cushion on first place than the Cubs, who enjoy a 4½-game edge over the second-place St. Louis Cardinals and five-game lead on the Milwaukee Brewers entering the second half of the season.