syl

Club. Ruining the communication for 3 ruffs (heart, club, heart) for a spade endplay having spade QTx in hand.

Club. Ruining the communication for 3 ruffs (heart, club, heart) for a spade endplay having spade QTx in hand.

...or just a mistype. Or 10 Vp penalties?

To be honest trusting in clubs (intending to put the Q in if ducked) helps also when LHO has Kxxx and J drops from the other side.

I ruff (high)+play the ace of trumps. Suppose they both follow. Small trump to dummy, then: A) If both follows hearts from top, if nothing interesting happens 3. heart hoping to find heartQ+clubK together, or if LHO won club guess... :) If LHO had 3 trumps heartJ from dummy, intending double finess. C) If RHO has 3 trumps club ace club, hoping KJ or KJx (or Kxx.... and duck) at LHO, and playing for heart drop if no success in clubs. Assuming hearts are 3-2 (2 on my left) double finessing or just running the jak and playing for drop if covered are equal chances, playing for the drop is slightly superior, the latter helps even when the Q falls from the other side. The advantege of the double finess is that it caters also DTxx onside-very inprobable if LHO had trump shortness.

As far as I have seen it crosschecking IS required using Bridgemates. Thats another issue that some players are lazy to control and let NS to do it alone, others quicly hit double OK so "doing" the input and the checking the same time.

GD

What about winning the fist trick, leading another diamond, unblocking the ace of spades and leading a club. West cant lead spade or diamond at this point as dummy has enough tricks. It also seems a wrong idea from east to overtake the king of clubs as 5 club tricks+an additional heart in the engame (even with a heart exit after the club ace) is enough for south. So after the club king west has to lead a heart. a) Small heart. If east takes it and returns either a club or a heart the club suit will be established, the heart suit blocked ie. the queen falls and both hands will be high. If east witholds the ace the jack will win, club ace knocked and even with a club exit ew will be unable to score more then 2 heart tricks. In some positions declerer has to withold a high club to protect the dummy to be (pseudo) squeezed. b-c) 10 or q ducked by east creats a similar position mentioned above.

Carding= Leads + Signals Leads= Opening lead+Subsequent leads Isn't it true?

Serious 3NT is used in GAMEFORCING situations, when the trump suit in a major is agreed and we are at the 3 level. In your sequence 3NT should be a proposal of final contract, say 5332 hand cca 14-16 HCP, especially when you hate to open 1NT with 5 cards in a major suit.

What about a slightly overbid 2♣♣? This rebid problem was known at the beginning, unlesss pd responds 1♠,when I can describe my hand with 3NT, I'm in trouble.