Final of the French Ladies Selection.

Bessis and Neve are defending against 6 clubs. Bessis leads the king of diamonds. Neve plays the jack and Bessis switches to a trump. wtf

In fact I heard about this problem many times before. How do you encourage with AJTx playing standard signals? Jack or ten? There are advocates for both. The tenners says that the jack should show jack-ten. The jackers say you should encourage with the highest from a sequence. The jack seems more natural to me but I hardly play standard signals.

Anyway, I think in this position North should overtake the king if there is the slightest possibility of different opinions. The chance that the king was unsupported was much smaller. Still this trump switch is hard to understand.

I would blame the two players 90%-90%.