| |
BGonline.org Forums
"Too good and not good enough": Two common mistakes
Posted By: Timothy Chow In Response To: "Too good and not good enough": Two common mistakes (Sam Pottle)
Date: Friday, 12 February 2010, at 3:33 p.m.
Sam Pottle wrote:
ND > DT is precisely what I mean by "not good enough", so I'd call it too good and not good enough despite it being a pass.
Of course everyone is free to use their own terminology, but let me again emphasize the point I was trying to make in my original article. If you get into the habit of describing a position as "too good and not good enough," then you risk falling into the error of concluding that a position is too good and not good enough just because there are some pairs of rolls that leave you too good and other pairs of rolls that leave you not good enough.
This is a subtle but important distinction. When you're contemplating a doubling decision, it is natural (and correct) to think about what the next two rolls may bring. There may be market losers, and there may be what I'm calling market freezers (which leave you either too good next roll or not good enough next roll). You don't want to fall into the following trap: "Hmmm...is this perhaps a position where I'm too good and not good enough? Let's see; I have some bad rolls that will certainly leave me not good enough. I also have some decent gammon chances, and for most rolls I'll retain those chances or improve them slightly. Since I'm 2-away, doubling would make my gammon wins worthless. So it looks like yes, I am too good and not good enough."
That reasoning is fallacious, or more charitably, it is incomplete. Firstly, retaining decent gammon chances is not the same as being too good next turn. Secondly, you need to consider market losers as well as market freezers, and weigh them against each other. The result might be that you should double, in spite of the market freezers.
It is important to distinguish between the statements
1a. I have market freezers that leave me too good next turn, and
1b. currently, my ND equity is greater than my D/P equity.Similarly it is important to distinguish between
2a. I have market freezers that leave me not good enough next turn, and
2b. currently, my ND equity is greater than my D/T equity.When I make these statements in broad daylight, they may seem obvious, but I have seen several analyses that make these mistakes beneath the surface. For example, in Kit Woolsey's article on the five-point match, he considers a certain 55 opening blitz at 2-away/3-away (62S-55A I think). He correctly argues that the leader's edge in this position is largely due to the gammon threat, and doubling nullifies that advantage, so the leader should not double. However, Woolsey then goes on to say something like, "Even if the trailer were to mistakenly pass, he would probably still be better off than if the leader had just played on." In other words, Woolsey thinks the position is ND > D/P > D/T. I can't find my rollout right now, but I'm pretty sure this is very far from being true. Common sense should tell us that it's very unlikely that the leader's gammon chances after a 3rd-roll dance are so high that ND > D/P, even ATS. My only explanation is that Woolsey incautiously fell into the trap above.
| |
BGonline.org Forums is maintained by Stick with WebBBS 5.12.