Draw rate, wins
Final draw rate was 75%. In the superfinal last season it was 89%, many more decisive games this season, more fun to watch. There were no black wins, only a few of the openings (one?) had a black bias and all these games ended in draws.
The three most common game termination causes were:
35% - TCEC draw rule
24% - TCEC win rule
24% - TB position
Moves per game
The games were a little shorter than in stage 3, draws were usually shorter than decisive games. Another example of the 'superfinal draw effect': high level + drawish games => short draws.
Time per game (hours)
Games were longer than in stage 3 by about an hour. This agrees with the addition of 30 minutes to each engine's clock. However it contradicts the 'superfinal draw effect'.
The first letter of the ECO codes of the superfinal openings was distributed as follows:
If we use the opening 'family name' (using format FAMILY_NAME: VARIANT....) the top 3 are:
Sicillian - 14 times
French - 8 times
King's indian - 8 times
Spanish - 8 times
The number of predetermined moves varied depending on the opening, the opening lines were usually quite long. All the reverse pairs had the same ECO code, in 4 openings the full opening
name was different.
Reverse pairs, wins
There were only 3 cases of an opening with two white wins, potentially a biased opening. This includes the notorious game 17. All in all excellent opening choices.
Reverse pairs, same moves
How many plys did the engines play after book until the first divergence in the reverse games?