If there are more spots in the MLB playoffs, it’s better, right? Not so fast

This is all. The final stretch. The last month of the 2021 baseball season is coming. Everything has been built to get there.

The degree to which that series of promotional clichés takes hold of you may depend on the year it came from. Let’s say you’re looking at this year’s rankings through a 1965 lens, or actually any 1901-1968 lens. There are two leagues and no divisions or wild cards, so it all depends on finishing first. It’s a pennant or nothing.

Through that lens, there are five teams seeking two spots in the World Series. In the American League, the Tampa Bay Rays have a good six-game lead over the Houston Astros. Everyone else is far enough back that if any of them caught the Rays, it would generate some “miracle” headlines.

The National League is tighter, with the Los Angeles Dodgers and San Francisco Giants locked in a classic pennant neck-tie on the 70th anniversary of their great career in 1951. But don’t sleep on the Milwaukee Brewers, who are just 3.5 from Frisco. Everyone else? It’s waiting until next year.

The narrative changes when you change the historical lens and compare the 2021 results with the formats of baseball history. Let’s prorate the current standings for 162 complete games, assuming current winning percentages hold until the end of the regular season schedule. Suppose also that any team that is seven games or closer to a playoff spot on the prorated standings is considered a contender.

Given those assumptions and the 2021 prorated ranking, here is the number of contenders we have in each format:

1. Two leagues, no divisions or wild cards (1901 to 1968): 5 contenders
2. Two leagues, four divisions, no wild cards (1969 to 1993): 8 contenders
3. Two leagues, six divisions, two wild cards (1994 to 2011): 16 contenders
4. Two leagues, six divisions, four wild cards (2012 to 2019, 2021): 16 contenders
5. Two leagues, six divisions, two byes to top seeds, 12 wild cards (rumored proposal to expand playoffs): 19 contenders
6. Two leagues, six divisions, 12 first and second places, four wild cards (2020): 19 contenders

In the real world, the only one of these scenarios that matters is No. 4. That is the current format, the one that has been in effect every season since 2012, except for the ad hoc system we support during the 2020 campaign shortened by the pandemic.

Our question for today: What are the pitfalls and benefits of changing that format, given the current level of top-down competitiveness throughout the game?