TCEC S21 L2 Underway; CCC Unorthodox Openings

Two weeks ago, in TCEC S21 L4 Underway; CCC Opening 'Specials' (May 2021), I wrote, 'The TCEC is vrooming in high gear; the CCC is stuck in second gear'. Two weeks later, copy that. The situation last time can be summarized as:-

TCEC: The Qualification League [QL] results were announced in Chessdom.com. League 4 [L4] should finish in the next day or so, although the top four engines have an insurmountable lead over the next group. • CCC: The site launched into a series of events based on specific openings. The first was 'Caro-Kann Special' with four engines.

The current situation of the world's leading engine vs. engine ongoing competitions is an evolution of that summary.

TCEC: Chessdom.com issued two reports on L4:-

• 2021-05-22: "The failed triumvirate report" (chessdom.com) • 'An epic, a tragedy and a drama are developing at the [TCEC]. Happening at the same time we have a race for the first place, a race for the last qualifying position, and a race to avoid relegation.'
• 2021-05-25: Booot kicks into high gear, wins TCEC S21 L4 (ditto)

Minic won L3, a half point ahead of Booot. L2 has finished a quarter of the scheduled games. Only one of the L3 qualifiers is currently in the L2 top-4, but it is too early to make predictions. One of the minor changes introduced for S21 is a 'DE' value displayed with an engine's score; e.g. Minic's current L2 score is '4.5 [0]', where '[0]' is its current 'DE' value. The !commands explain,

!de • Direct Encounter is a tiebreak calculated from games between engines that have same amount of points. See !tiebreak

!tiebreak • For all Leagues, Playoff and Premier Division the tiebreak order is 1: Direct encounter [...]

L2 should finish this week

CCC: In the most recent off-week engine post, CCC PGN IV (May 2021), I looked at 'Sicilian Najdorf Special', the last of the five events using a specific [thematic] opening. After the thematic events, the site continued with 'Belgian Stew', 900 games starting with what appear to be randomly selected openings; and 'Saragossa', 300 games starting, 1.c3.

The site is currently running a 'Double Bongcloud' event starting, 1.e4 e5 2.Ke2 Ke7. The 392 games should finish this week. After that we should probably brace for more unorthodox openings.

[For further information from the various stakeholders in the engine-to-engine events, see the tab 'TCEC/CCC Links' at the top of this page. • NB: Leela = LC0 = LCzero]