>As some others already wrote, if you miss a double and lose 0.2 equity, you need positive luck to arrive at the same situation again.
No. The point is: how much do you loose if you postpone a double for 1 (or more rolls). If you have a .2 better equity if you double now, that doesn't mean you loose 0.2 by not doubling now but if you double never. So what does it cost do double one roll later. See here:
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Moneygame Green to move. Cube Action? | ||||
Green is better off doubling by about 0.1 but what costs it not to double now? Absolutely nothing. The position isn't ideal, but at least it should be clear what I mean.
Another example. You find an ancient vase in your attic. It is in bad conditions, so you let a restorer prepare it for $1000. You go to a fair and at the first day someone offers you $1800. You deny. Your wife tells you: "You stupid, you just lost $800". At the 2nd day you deny an offer of $2100. At the 3rd day you deny $2000. So far you "lost" $2900?? At the 4th day you sell it for $1900. So how much did you lose? Nothing, $2900, gained $900, $200?