NORTH
 9763
 9
 A763
 AQ65
 T842
 J7432
 T5
 T8
  5
 AQT6
 KQJ2
 J942
  AKQJ
 K85
 984
 K73
Dealer: South    Vul: NS   MP Scoring

West

Pass
Pass
Pass

North

2
4

East

2
Pass

South
1N
2
Pass

 Lead Directing Gamble 

East's solid diamond honors, at favourable vulnerability, suggested a 2 bid of some risk with 2 as a bolt-hole 2nd chance.

West might otherwise have led longest suit rather than top of a doubleton diamond and South might then come to 1 heart ruff, 4 spades, 1 heart, 3 clubs and 1 diamond (at least).

West led a diamond won in dummy.
Two rounds of trump were drawn, the A won and a heart advanced towards hand.
East won, cashed two diamonds and the fourth round was ruffed high by declarer promoting West's T, down one: 1 spade, 1 heart and 2 diamonds.

How would would North South reach a possible 2X contract (other deals without alternative East West heart contracts)?

South could double with 4 good diamonds (or longer) and could pass with 3 good diamonds (or 4 poor ones) and North could suggest alternatives.

What other meanings would there be for South's Pass and later action?