Robertie on DMP

I found a three-part series on DMP by Bill Robertie from 2002.  These were published on Gammon Village.  This mostly agrees with Stick's advice, with some exceptions additions noted below.  What follows are the highlights from these articles. 

General

1.      Blitzes become much weaker at DMP. When you launch a blitz, you're trying to win a lot of gammons at the cost of a mistimed position when the blitz fails. With no gammons counting, all you get is the bad timing.

2.      Back games and ace-point games are much better than normal. You can't get gammoned or backgammoned, so you're free to hang around for the very last shot. Your real concern is to preserve your timing so that your board doesn't collapse.

3.      Anchors lose half their value. In a money game, anchors serve two functions: they prevent you from being primed, and they prevent you from being gammoned. At DMP, they serve only one of these functions. Plays where you boldly run off an anchor are therefore much more common at DMP.

4.      Primes become stronger. Running from behind a prime, even at the risk of being attacked, becomes commonplace.

5.      Middle game tactics.  Plays that might take your winning chances to about 75%, which are extra-powerful with a cube in play (where getting to 75% is equivalent to winning the game), now don't contain any special bonus. However, plays which, when they work, boost your winning chances into the 90+% area, are especially powerful. While these plays may represent excessive risk and overkill in a game with a cube, here they give you a chance to snuff out resistance altogether. DMP is a battleground of big plays, where both sides must be willing to put the game on the line once they have favorable odds.

Opening Rolls at DMP per Robertie

In a nutshell

Split with aces: 51S, 41S, 21S

Sixes: Run with 63R, 64R; Split with 62S

Split with other numbers: 54S, 52S, 32S, 43S

Discussion:

I am not sure I agree with Robertie on aces. 

For example, he writes don’t slot with an ace.  He argues the key to DMP opening play is Move your back men quickly! His logic - avoid being primed, and risk getting hit and falling behind – seems plausible but may be wrong. 

I show 21$ as correct, and 51$ and 41$ essentially tied on Stick’s site (bgonline.org).  I believe the reasons for slotting are: 1) aces are worst racing number, 2) priming is a great DMP game plan so let’s put the checkers where you want them. 3) The downside is lessened somewhat by the fact that backgames are a viable fallback strategy, 4) you believe you are the better player and want to complicate!!.

I believe 43Z (reverse split) is slightly better than 43S.

Early Game Play

Basic Game Plans

1.      Escape your back checkers and win the race.

2.      Build a 6-point prime against a single checker and roll it home to victory

3.      Contact game plans (blitzes, backgames. etc) should be avoided

Robertie argues that when neither side has much structure your first priority is to run.  Escaping a checker is “easy” while building a prime is “hard.” 

Robertie introduces the concept of splitting to a key point in order to induce an exchange of hits.  As always, the gammon threat is irrelevant so the danger of coming under the gun or getting blitzed is lessened.  Exchanging hits gains in the race.  Meanwhile, your split checkers control his half of the board and you may be able to build your offense (think prime) on your side of the board.

Robertie introduces another idea – leaving a blot as bait when way down in the race.  This is a gambit idea – you hope to get hit, anchor somewhere in his home board and win later. 

I am not sure I entirely buy Robertie’s ideas from this article either.  A well-timed backgame is a favorite to win and thus can be a viable strategy.

Middle Game Play

Key Ideas

1.      Don't overextend to try for a blitz. Blitzes don't win gammons any longer, so they're not nearly as strong a game plan as in a money game. Instead, look for good, balanced positions that can be converted to a good race.

2.      A six-point prime is a huge asset, even stronger than in a money game. As a six-prime becomes a possibility, you should be willing to take larger-than-usual chances to complete it.

3.      There's no cube, so forget about making measured plays that give you a strong double when they work, but minimize the downside when they don't. Look for plays that go for the kill.

4.      In the ending, look for plays that give you any kind of an increase in winning chances, even if they involve huge gammon or backgammon risk.

I think the most valuable tidbit here is to keep in mind you can never the double the guy out.  In money game, you get to 70% or so and just the double the guy out, but at DMP you have go all the way to 100%  Lesson – think about the long-term gameplan.

Again, gradual improvement with the idea of an efficient cube is out!  Rather, go for the kill and try to achieve a gin position as quickly as possible.