Find the Queen by Hiron (Great Britain)

For a long time, I have held the view that it is a good bet to bid a grand slam that depends upon guessing the where abouts of a missing queen of trumps. The theory is - if an opponent leads a trump, your problems are solved; if they do not lead a trump, you play the opening leader for the queen.
Although my partisan feelings were outraged at the result, I was interested to see my idea applied on this deal:

N/S Vul. Dealer East.

                        S Q9
                        H QT97543
                        D 532
                        C 4
              S KJT7              S A853
              H KJ6               H A82
              D AQJT              D K7
              C A8                C QJ52
                        S 642
                        H -
                        D 9864
                        C KT9763

In the Open, everyone reached a slam. 6NT, (slightly inferior, as you need to guess the spades as well as finding the King of clubs well placed), was likely to fail. Declarer, lacking any clues from the bidding, can cope with S Q9xx in the South hand, but not in North.
At least one table in 6S, declarer played the percentages in the trump suit, but north was on the ball, after winning with the SQ, he brightly returned a heart for South to ruff.
Now the spotlight turns to the Ladies match between Great Britain Ladies and Iceland. Kay Preddy and Jill Casey ended up in the notrump slam and must have been well satisfied when an against the odds play in spades brought home the contract. A big swing was anticipated and it duly materialized.
Anna Ivarsdottir and Ljosbra Baldursdottir bid 1NT - 2C - 2S - 4NT - 5H - 7S. Five hearts showed two aces, but no queen of spades. Following my suggested strategy, West had no problem. Neither did East in the play, after Sandra Landy led a  dutiful trump - and no one could possibly blame her.