It's unethical and against the spirit of the laws and the game to think when you shouldn't in order to mislead the opponents. So when you hold a singleton you should play it right away and not think before playing it (of course there are two issues, you shouldn't play TOO fast if you're a defender and you CAN think when the singleton is in dummy). Somebody told me I 'misbehaved' in this position: Dummy: ♦Q9x Declarer's hand♦AKxx RHO led a diamond and I hesitated a bit (apparently, I don't remember, and I didn't do it on purpose anyway) eventually playing the Ace. LHO (and probably RHO, too) was fooled into believing his partner had ♦K; no damage resulted but I was told off, i was told I HAD to win with the ♦K in order to make the situation clear. I asked somebody at the club and they said I DIDN'T have to play the ♦K but that I did have to say something like 'Sorry, I didn't have anything to think about'. What is correct in this type of situation? Now for the bonus: 1♠ 2♦ 2♠ Pass 4♣ Pass 4♠ All Pass I led the ♦A (Kelsey's style): [hv=d=s&v=n&n=s6xxhxxxdj87xcaj9&w=skthjxxdakxxxxckx]266|200|[/hv] Your lead catches only small cards. How do you continue? [hv=e=sjxhtxxd5ctxxxxxx&s=saqxxxxhakqxdqxcq]266|200|[/hv] Well, it involves a mistake from declarer (but a mistake many would commit). I couldn't make this defense though as my partner played the small diamond like a lightning (almost before dummy went down) and so I didn't want to take advantage or be unethical.