Constructing double-dummy problems

A while back I posted this double-dummy problem. At the time, I promised some follow-ups.

At some point, I offered the hand to Hugh Darwen, author of a great book and website on double dummy problems, both called Bridge Magic. I constructed the hand to demonstrate an interesting squeeze ending, but was interested to learn that to a problem connoisseur that was not enough: it lacks precision. He identified 2 problems:

1. There's some freedom to the order in which early major suit winners may be cashed.

2. More importantly, when North pitches a diamond on the 3rd heart the play becomes significantly more precise and interesting (i.e. wouldn't it be nice for the problem to be forced down this line).

Given this feedback, I tried to modify the problem somewhat, but was unable to address both issues at once. Of the 3 constructions (the original linked to above, and 2 below respectively addressing the above comments), I think the last one below is the most interesting.

In all cases, you're to make 6NT after the ♦Q opening lead.

		♠	A K 8 2
		♥	A K
		♦	3 2
		♣	A 8 4 3 2
♠	J 9 7 6 5 4			♠
♥	J			♥	10 9 8 7 6
♦	Q J			♦	10 8 7 6 5 4
♣	10 9 7 6			♣	Q J
		♠	Q 10 3
		♥	Q 5 4 3 2
		♦	A K 9
		♣	K 5

On a non-diamond lead, there's a red suit squeeze (duck a club). On a diamond lead, declarer must win, play ♠10, ♥A, ♥K, ♠Q, ♥Q. However, either a club or a diamond may be pitched on the last heart, and the diamond pitch is more interesting.

		♠	Q J 10 3 2
		♥	A K
		♦	2
		♣	A 8 4 3 2
♠	9 8 7 6 5 4			♠
♥	Q			♥	J 10 9 8 7 6
♦	Q J			♦	10 8 7 6 5 4
♣	10 9 7 6			♣	Q J
		♠	A K
		♥	5 4 3 2
		♦	A K 9 4 3
		♣	K 5

On a non diamond lead, there's a nice delayed-duck squeeze in the red suits. On a diamond lead, declarer must win, ♠A, ♠K, ♥A. Now, major suit winners can be cashed in any order so long as the last heart comes before the last spade (imprecise). This serves to make the play a little more interesting when East unguards hearts (♣A, ♣K, heart). Also, the diamond menace against West is a little more interesting, requiring a throw-in to give it full force.