Correct. If there happens to be a tie within a division at the end of the regular season, the division winner is determined by head-to-head matchup. Since divisional rivals play each other an odd number of times (13 this season), one of those tied teams will win the tiebreaker.
Back when I was still following baseball and reading the standings in a dead-trees paper, GB (games behind) was always the order of ranking. And by that measure, the 3-0 team would be half a game behind the 5-1 team, despite having a better winning percentage.
These differences rarely happen outside the first few games of the season, when not only do extreme W/L percentages crop up, but a combination of weather issues and more open dates result in one team having played three or four more games than another.
But the 3-0 team would be half a game ahead of the 4-2 team, so as you said, the 3-0 team would lead either way in that scenario.
Now that you mention it, perhaps it was ranked the other way around, ie by games behind instead of winning %age. Or maybe some sources did it one way and others another. But what you say rings a bell.
Yes, and we would see a strange listing in the standings, with the 3-0 team in first place, but 1/2 game behind the 5-1 team. Standings are always ordered by win percentage.
3-0 is indisputably better than 4-2 by any measure anyway. It’s a better winning percentage, and it’s half a game better by the games ahead method.