The great Charlie Ursitti painstakingly compiled data on 14.1 through the golden years. His PDFs of this data can be found online if someone wanted to dig through them for this comparison. From roughly scanning the data for the 1920s (my favorite era), the tournament winners looked to average 5 or 6 balls per inning.
[Edited with updated analysis]
I fed Charlie's data into ChatGPT to do an analysis. It says:
For 1920s:
1) average BPI for top 5 players was 4.56
2) Ralph Greenleaf had the top average BPI throughout the decade at 5.697
For 1940s:
1) the average BPI for the top 5 players was 8.78
2) Mosconi averages 10.37 throughout the decade (Greenleaf managed 7.58)
For the 1950s:
1) average BPI for the top 5 was 10.767
2) Mosconi's average BPI was 18.54, the top of the decade
For 1970s:
1) average BPI for top 5 was 12.216
2) Steve Mizerak had the top average through the decade at 14.41
Note: I don't 100% trust ChatGPT's calculations here, as I think it's missing some data from Charlie's PDFs. But it looks generally accurate based on the 5 minutes I was willing to double check. As others have pointed out, there were radical changes in equipment starting in the 1940s (better cloth, rails, smaller tables, better balls, uniform equipment at tournaments, etc.) so I don't view this as an accurate way to compare Mizerak to Mosconi. But it does show that BPI correlates with winning lots of championships.
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