Heaven forbid, you pre-empt and then later decide to enter the auction again. This typically, not a deadly sin, however, is usually far from ideal. If one decides to pre-empt, one must pre-empt to the limit of one’s hand right away and forever hold one’s peace. As always, though, one must bid if partner makes any call other than a raise of the pre-empt suit.
There is, however, like almost everything in bridge, exceptions. There are two. The first is if one is two-suited (in the minors) and the other is when partner makes a raise (using Law of Total Tricks), then one is allowed to make a further call. When I say allow, I mean allowed by good bridge sense and not allowed by the opponents who rather you not pre-empt at all.
The ideal pre-empt is one that pre-empts the opponents when they have points and cautions partner that your hand is not a suitable dummy except in your own suit(s) when he has points. The pre-empt cannot make game anywhere if partner has a minimum opener or less.
The Bidding South picks up his hand and the alarm bells go off because he has only one card in the major suits. He pre-empts Three Diamonds in first seat. West overcalls Three Hearts and East raises to game. North is silent waiting to see if the opponents bid game.
At favourable vulnerability, South is not done with the bidding. He has a two-suited hand with no defense. He bids Five Clubs.
West bids Five Hearts and North bids Six Clubs. If the opponents bid Six Hearts, he will then bid Seven Clubs. He knows he can defeat Seven Hearts and his double fit in the minors with partner makes the sacrifice a good bet.
East has values in Clubs and decides to double and not try Six. Had the Club King been the Heart Ace, Six would have been a good bid.
Opening Lead: West leads the Spade Queen. He does not want to set up declarer’s side suit so he does not lead a Diamond.
The Play: Declarer ruffs the opening lead and takes the Club Finesse. If Diamonds were split three-nothing then the Club Queen to the Club Ace and then a small Club is the better play. However, declarer ignores the low percentage possibility and takes the finesse. Declarer loses a Club and two Diamonds for down two and -300. Down one would have been exceptional so the Club finesse was worth the try. South’s pre-empting gave the opponents 300 instead of 650.