Play NT or a 5-3 Major Fit?

There is a recent investigation on the topic in the title. The short summary was: 

No singleton, play NT.

They say it is usually better to play in NT with 50% more chance to win. I applied it in the case above, and it did work. No idea how reasonable that is on the long run.

So, here is a counterexample to warn you. Especially, 4-4 fits are vulnerable to the application of the mentioned rule. They do not provide 5 quick tricks. Moreover, the rule was tested for hands with combined 25-29 high card points. In the case above, the missing stopper in hearts adds to the problem.

Of course, the rule must not be judged on one case alone. In the hand above, it fails after a club lead because the spades do not break. 4♠ is better. It even makes an overtrick.

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