nige1, on 2013-July-27, 17:49, said:
The law should treat slips of the mind the same way as slips of the hand. The law would be simpler and fairer. Law-abiding players would suffer less of a disadvantage. Players would still ask the director to waive the rules for handicapped players, as they've always done. A fetid mire of pointless controversy would be drained.
Even if it did, it wouldn't change the ruling in the present case. The present case was clearly due to the player changing his mind on seeing the J, which is a deliberative change of mind, not a slip of the mind by any plausible definition.
But I disagree with you, for two reasons.
First, slips of the mind are qualitatively different from slips of the hand (or tongue or pen). In the latter case, the hand (or tongue or pen) accidentally does not do what the mind tells it to do, and we allow a correction if it is clear that is what happened. But in these latter cases the defining factor is what the mind directed. When we allow a change of what the mind directed, that is qualitatively different.
Second, clearly deliberative changes of mind should still be disallowed. So is it even practical to define a "slip of mind" so that is evidently different from a deliberative change of mind? I don't think so. So I think this is impractical.
Most games there are no "undos". Many people think bridge would be better if it was the same. Backgammon is an exception, which is facilitated by the fact that a move has an "end signal" when you pick up the dice, and nothing before that is complete.