Steve, I have often suspected that Snowie messes up on match equity calculations. I reported the following cube action problem on the Snowie Forum, where I was equally baffled with Snowie's calculations. In nearly two years, nobody has ever responded with an explanation of why Snowie and I get very different conclusions. Perhaps you can figure it out! See: http://bgsnowie.com/forum/mostra.dhtml? f=bgsnowie/23&threadid=7292

Regarding the checker play problem, it may be that Snowie is calculating wrong, or not; it is more complicated. Snowie's evaluation is not just a crunching of the wins and gammons, but also factors in the value of cube access with the different plays. Even with the high doubling point at the score, there is still value in being able to offer an efficient double. It seems to me that running the back checker out creates maximum volatility. White's attack will either succeed or fail but it seems unlikely that white will ever get an efficient cube out of the resulting positions. With green maintaining the ace point anchor, white obtains scenarios where he escapes the back men and still stands to lose a fair share of games against green's ace point anchor, but in such positions, white will be able to turn the cube somewhat efficiently. The cube value may in Snowie's opinion offset the cubeless match equity difference.