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3D was also alerted as "showing some bid hand, and when there are two suits bid by the opponents should show the suit he has stopped rather than the one he hasn't"/
I am guessing this is a typo and should read: "some big hand," ?
If so, the auction to West's perspective should be based on some long, good suit, obviously not hearts or spades due to West's holdings in these suits, not clubs due to the bid by South, so that leaves diamonds. West bid his hand normally, showing hearts against a normal t.o. double and then the club stop when he thought he was facing a strong hand - and East pulled....the key issue here is whether West knew from past experience that this pull showed not a strong hand but a weaker hand with simply long diamonds? In other words, would the pull normally be forcing and a slam try perhaps or just expressing doubt about the final contract with a stong hand, a singleton club, but non-solid diamonds?
If East/West are complaining about the 1D opening, little can be done unless this is a pattern of opening the better HCP minor regardless of length and giving incorrect information knowingly. The only real damage is that a 1C opening would have allowed a diamond overcall - sorry, but unless it is specifically agreed not to do this then North has violated system and he took the risk that partner as well as defender's could be misled.
Looks like a good case for a "no harm, no foul" call to me with a mental reminder to watch and see if further bidding indicates agreements undisclosed.
Winston