The hand opposite occurred recently and was not handled well by the field. Only four pairs bid 6S and 9 pairs played 4S or 5S. Since 7S is cold, these would have been disappointing results for all concerned. At one table, East passed since they weren’t playing any two suited openings. South made a clear cut opening showing spades. Passing is definitely too passive and there is too much in the side suits to open a weak 2 bid. North should respond showing the diamond suit since it is likely to be a source of tricks in the play. This is much better than a splinter bid in clubs. If NS are playing a 2/ 1FG or 2/ 1 forcing to 2NT, South rebids 2S showing a minimum hand and intends to show the diamond support on the next round. However, North leaps to 4C next which is a clear, although surprising, splinter bid agreeing spades ( since 3C would be natural and FG). South needs to show slam interest now. Giving North just the KS and KD suggests 5 spade, 1 heart and 4 diamond tricks which is enough for game and North has more than just two kings. A cue bid of 4H, showing a control in the suit, expresses slam interest ( without slam interest, just bid 4S). This is wonderful news to North who bids 5C, voidwood, asking about keycards outside clubs. South shows one and then shows the QS. North has not been able to find out about the important QD so stops in 6S. Could you bid 7S? If South had taken control, they would miss finding either the club void or the KD. Suppose EW quickly raise the auction to 5C? South is not likely to have wasted values in clubs so North sees 16 and South has 11+ hcp. So NS are missing, at most 3 points in the other 3 suits so must have at least three of the AKH, QS and QD. North can easily bid 6S and 7S if they feel lucky.