Suppose you were playing this week, with the necklace extra. When would you use the necklace?

I would play it in the first box of the final round, like Jim did today. So would majority of others, judging from the comment we've had over the course of the week.

But what would you do?

(You have seven days to vote).

4 box.

I'd use it second in round 2. I'd explicitly say as much (and give the necklace to the player who was set on my system to open the second box of round 6, regardless of who it was), and trail it before the game.

And then hope I get a 5-box offer generous enough that I deal anyway.

I've gone for "depends on the board"!!

Same here, although I think 4-box is the optimal time to use it, on average.