Hi friends, all comments and questions are welcome

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Precision club[/glow]
Unlike SAYC, Polish club, French five major ... where most of bids and gadgets are standardized, precision club have lot of variants. I will try to explain in this post the reason of same great diversity. For experienced/advanced players - please read Ron's (The_Hog) post in this topic - i agree with all that he wrote there.
General idea of Precision club is VERY limited openings(11-15hcp). The result is opening with 1CL with all other strong hands. It is possible to open 1DI or even Strong pass instead of 1CL and will not change general idea.
Why do you need limited openings, if you can play well with 12-21 opening? For fun ofcourse too ;D. But VERY important is same opening made you "commander" of deal. ( I strongly recommend you to read Robson/Segal book "Partnersip bidding" about wining strategy of such bidding in competition ). "Commander" can make GREAT tactical and bluff bids, like: strong "preempt" raise to 4 level, waiting opponents to bid for dbl them; crazy "preempt" without fear from strong opener; bluffing in suit and close to game; ... If you dont like tactical and bluff bids - DONT play Precision club!!! If you cant use potential of limited openings and receive all negatives from 1CL hcp opening - you will lose much more often, than playing simple SAYC.
Basic Precision ( C.Wei version ):
1CL: 16+hcp, any
1DI: 11-15 hcp, 2+DI, without 5 major, weak NT, 6+CL, 5+CL-4 major
1HE/SP: 11-15hcp, 5+HE/SP
1NT: 13-15hcp, bal
2CL: 11-15hcp, 5+CL-4 major or 6+CL
2DI: 11-15hcp, 4414, 4405, 4-3-1-5/3415 with bad CL, singleton or void DI
2HE/SP: weak 2
2NT: 22-23hcp, bal
Notes:
- Strong jump shifts to 1DI/HE/SP opening: 16+hcp, slam interest
- 1DI-2DI response is natural 2/1 forcing 1 round
- 1CL-1DI response except normal negative 0-7hcp may include "impossible negative": 8+hcp, 4441 any singleton
Advantages:
1CL opening allow low level auction and lead to easy bidding of games and enough space to investigate slams.
Limited 11-15 opening often lead to quick arrival to game, hard for defence due to lack of information.
Reverses of limited opener is distributional only and is possible to reach games and slams with few hcp, based on good placement of it.
Disadvantages:
1CL is often target of special defence like multi bids, bluffs and crazy preempts. This lead to unpredictable result for both sides, but more often lose 1CL opener, because he have statistical game on his line.
1DI with 2-3 cards sometimes lead to bad contracts in DI.
2CL opening lose much bidding space and missing game in major is possible, if responder dont have enough hcp to bid.
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Versions - HCP limits[/glow]
Generally 2 types:
1. Change 1NT to 15-17(14-16)hcp. 1DI opening include 11-14 hcp, bal. Main idea is to make 1CL opening stronger, easy to rebid in competition too. Some of versions extend limit of 1DI opening ( sometimes 1HE/1SP too ) to 17hcp. Some of them open 1DI even with void. Example of same version is "Power Precision" - Sontag and Weischel. Most popular in Bulgaria is similar version with 2DI multi and 2HE/SP dutch.
Result -> 1CL opening is better, but 1DI opening is worse. Instead of 1 bad opening - 1CL you have already 2 - 1CL and 1DI.
2. Change limits from 11-15 to (8)9-14(15). Reason is to open more often, giving information to partner early and increase chances for him to make right decision. Example of same version is "MOSCITO", can ask Ron (The_Hog) or Richard (hrothgar) about.
Result -> 1CL remain vulnerable; extend of limits decrease possibility of quick arrival and tactical bids.
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Versions - Opening suits[/glow]
1. Change 1DI to natural 4+ card ( Goren Precision). Include nicely DI suit in battle.
Result -> With often 11-12hcp, bal you cant open.
2. Change 2DI to 2HE. For opponents are more difficulte to compete or dbl, because 2HE often can be passed unlike 2DI. 2DI is free for multi ( weak 2 in any major ), Wilkosz ( weak 5+-5+ with at least 1 major ), Ekren ( weak 4+-4+ )...
2SP ( with multi 2DI ) can be used for any good pre-empt to 3 level, while direct pre-empts can be bad... One of best bulgarian experts - Boian ( he often play in BBO - nick PPilot ) play similar with 9-14hcp limits and 1DI 4+ cards.
Result -> May be best version of Precision and relative easy to play.
3. Change 1DI to 0 or 1+ cards. Reason is to free 2DI bid, because it rare happen.
Result -> 1DI bid include lot of variants, with 5+CL bad suit too, come very often and is very hard for bidding.
4. Change 1 major opening to 4+ cards ( MOSCITO ). Reason is 4 cards in major come more often than 5. You can find 4-4 major fit quickly unlike natural system. Opponents must overcall at 2 level unlike after natural 1CL/1DI.
Result -> You lose quick raise with 3 cards of 5 major opening. Your partner also must bid at 2 level. Sometimes cant stop at good 1NT contract.
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Versions - Responses and rebids[/glow]
1. Relay responses to limited openings or to responses of 1CL opening. Reason is that opener ( responder to 1CL ) already show some distribution and hcp limit and is more easy, if he continue to show, while responder just ask for it. By absolute information sometimes is possible to reach game or slam, hard or impossible to bid by natural bidding. Relay response also leave lot of responses free for limited bids, best for MP tourney. Lack of information about hand of player, who ask by relays, make difficulte lead.
Result -> If you are computer, best way is to play by relays ;D. Often counting steps answers to realys ( with fingers under the table :'( ) is so tiresome... In contrast to natural bidding ANY LITTLE MISTAKE normally lead to GREAT LOSS. Relays for game contract can lose chance for chocie of game - distribution and hcp limit is not enough, important also is pacement of H in suits. Dummy can be player who ask by relays and defence will be in same case on double dummy.
2. Transfer responses to 1CL opening. Most of time is better to play strong hand as after 1NT (15-18) opening. Also trsansfers allow nice relay

step in transfer suit. You can ask Dwayne Hoffman here in forum about Keylime precision.
Result -> Best way for answers to strong hand.
3. Control responses to 1CL opening ( Blue club ). Reason is number of H controls ( A and K ) often limit contract to game or sure slam.
Result -> 1CL opening already lose tempo, because not show any distribution. If responder also not show it, bidding is worse than natural system. Such response is also VERY vulnerable to pre-empt.
4. Asking bids from 1CL opening ( Super precision ). For strong hand is more easy to decide final contract by asking what it need for.
Result -> Bidding space is not enough for distribution, amount and placemant of H - not a perfect world :

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Misho