Chess is all thought out, the same with checkers.

What I mean is that there are no more strategic or tactical themes left to discover. The new "ideas" are simply new moves in old positions. A re-evaluation of "lines". Or maybe a new opening emerges. (Which often turns out to have been first played in the nineteenth century anyways.)

What of backgammon? Its theory seems to have kicked off in the 1970s and been added to in the 1990s and 2000s but are there are any new ideas left in it to be discovered?

I don't really think so. Given that the pros can play to a similar level to that of a bot which has played million of trial and error games, I don't really see how it is possible. When bots were first created there must have been a lot of theory development but the rate at which they improve has slowed down so I wouldn't have thought there would be any future groundbreaking themes.

The answer to this question has a lot to do with just what one considers to be "Theory/Strategy" and what one considers to be "Mere tactics".

In my view, the "theory" of backgammon was pretty much complete by the 1930s. Players of that era generally understood the basics of racing, priming, and backgames and knew the math of doubling and taking. It's hard to read Jacoby and Crawford's "The Backgammon Book" (1970) and point to any gross theoretical errors by the authors.

What has happened since then has just been a gradual increase in the tactical ability of the players. The level of play improved through the 1970s, and then again through the 1980s, and continued to improve through the computer era. As players got more experience and did more rollouts, first by hand and then using the bots, they refined their ability to make judgements between plays. When two good players argue about the merits of play A versus play B, they're rarely arguing about anything theoretical. They're just trying to figure out whether position A is going to play better than position B.

And that's fine! The actual theory of most board games is usually pretty simple stuff. The tactics are incredibly complex and hard to figure out. There's a general misconception that good players understand "theory" at some deep level, and because of this they are able to find good moves at the board by consulting their theoretical understanding. Actually they're good because they're tactically super-sharp and they have a huge database of knowledge about what sort of moves tend to work in what sort of positions.

So backgammon is (in my view) just as interesting as it ever was, but there are more very good players, so it's harder to win.

Robertie you might be able to answer a question.

In the “old days” 80’s and early 90’s - what was the distribution of playing skill level in the top flights of the big tournaments?

When I started attending the world championship top flight back in 1996 I discussed the posed question with a group of players. Almost everybody agreed that approx. 1/3 of the field would have a fair chance of winning the championship with a good run. 1/3 of the field would have to have the week of their life too win it and 1/3 would never (<1/1000) have a chance.

I myself believe it has gotten a lot harder after the mid 90’s. Now half the field can win it on a good week and maybe 40% can win it when running hot and 10% don’t stand a chance. Back in 2004 when I had the good fortune of running hot I played Wachel, Ekmark, O’Laughlin, Stegenborg, A. Williams, Guris and Noreen where at least 4 of them are really strong players and the rest are “just” good players.

Yes, I think you're essentially correct.

I try to play in the Las Vegas tournaments each year and in the Main Event I can't remember the last time I played someone whom I thought had no real chance to win. Perhaps I've had poor draws for awhile, but everyone seems to be either "world class" or "pretty darn good". You can however, have a nice edge in the minor events like the blitz, doubles, or seniors, where a lot of weaker players play.

Contrast this to the 1980s and early 1990s. From 1981 to 1994 I won over 80% of my matches in the main event of the World Championship at Monte Carlo, and I was a much worse player then than I am now. So yes, times have changed. When you can have a world-class player on your desktop to practice against every day, you're going to get very, very good. That's why 12 and 13-year olds can be grandmasters at chess.

thats a wonderful question....though the way you phrase that sound almost as if you are belittling the game of chess which is the ultimate game of intelligence. other than that--i agree with this post and feel its a great question!!

I was active back in the backgammon scene in the mid-90s, when the bots finally got good. Theory was very advanced at that point, but there were still a few things to figure out. Match equity was a hot topic (e.g. how to use the doubling cube in various match situations), and there were a few things yet to be discovered in checker play.

IIRC The publication of "New Ideas in Backgammon" by Kit Woolsey and Hal Heinrich in 1996 was the final attempt to plug some gaps in the theory of backgammon. After that, everybody said "F it" and went and played poker instead.