Structural Differences

 ACOL---->BETA

     

Preface:  A historical evolution

ACOL was the startingpoint for the evolution to BETA. Step by Step the evolution has erased its ACOLness and BETA is now a system in its own right.

 The initial important step was removing the concept of reverse - long considered the stumbling block that limits ACOL's evolution! This fundamental change could not be made without further complimentary changes: The most essential was reverting to strong Major 2 openings and a necessary futher change is the introduction of a Multi 2 in order to retain an ability to show weak Major 2's & also 19-20 Bal NT.

It was also noted that with the introduction of the 19-20  point range for balanced hands BETA could itntroduce 2 point ranges for strong balanced hands of 17+ HCP: jump rebid of 2N: 17-18, 2N opening 21-22, 2C opening and rebid after WEAK response of 2 a 2N shows 23-24 & 3N for 25+.... 2 point ranges represents extra precision.
Also implemented in early days was the Crowhurst 1NT rebid of 12-16 and a mandatory 2C inquiry if responder has 9+ HCP.

BETA still uses a 12-14 1NT opening BUT kimits it to at least 7 minor cards but a 4 card Major can still be held! So a Stayman 2C inquiry however a 2D response shows a 4 card Diamond suit and denies a Major opening Over any NT bid showing 19+ BETA uses PUPPET sequences are employed - every esponse is a transfer

Early on BETA introduced a relatively simple system for signalling and a style for leading too: see: LS.   Our preference was a system suitable for NT as well as suit contract, Simple to administer - not requiring any mental strain - or depending on having the right type of small cards!

Later we introduced our defence to strong club systems when Precision appeared or other strong club systems: TRAP over strong 1C openings and  bidding our shortage over a false 1mi;  Lebensohl, in turn got replaced by Rubinsohl -  more direct - used in defence of weak 2's and 1NT openings & also over interventions following our own 1NT opening. Note: in modern BETA when opponentss open better minor or minor openings that can be 2+ or 3+ cards we now have an exciting and agreessive solution:: see 1CResp.

Also in early days 2C sequences were structured in a 'Q & A' form: where the strong hand did the asking and the weak hand responds in 4 steps. Also replaced the iniquitious response of an almost automatic 2D response  to declare total of responders Aces & Kings counting K for 1 & A for 2: and responses became 2D:0; 2H:1|2; 2S:3|4 and rare 2NT:5+ this gives the 2C bidder a fair idea of the limit of the hand. Also in relation to 2C openings and almost all BETA openings a weak responder can expose his long suit 7+ cards when unable to give a positive reply to the 2C bidder and 6+ cards to subsequent question: -  the concept of 'Break-Outs'. It can be a great warning of a useless hand opposite EXCEPT if contracted in partner's long suit! In our 2C sequences 4N is NEVER blackwood - it asks the number of kings!

We also made an error by experimenting with provide special sequences for 3-suited hads. This experiment failed and is now long discarded as these hands are rare, 2%, and can be handled otherwise by our methods

One important adjustment was made for hands with 4-4 in the Majors to open 1H. 1H otherwise for 5+ cards in Hearts. This has proved magnificent. BETA is characterised uniquely as a 5452 system. 1H of course is 85%+ likely to be 5+ cards. BETA handles this 'multi' 1H opening without any difficulties - but with significant advantages in finding a Major fit if there is one by the 2-level regardless of being 4-4 or 5-3 or even 6-2. And this fits our approach that first will establish a Major game before a NT  game before a minor game of course not ignoring slams on our way!

BETA has instead developed powerful sequences to handle 5-5|6-5|6-6|7-6 hands as these potentially powerful hands are hard to show with normal methods -and eliminates the classical problem of  differentiating 5-5 & 6-4 for example.. This allowed for a more appropriate development for these special hands. Their introduction had a knock on effect in other bidding sequences making them also more precise in showing their shape.

While ACOL has expanded its frequency of use of a 1NT opening BETA has somewhat specialised it, reducing its frequency and placing more weight on our universal 1C opening.
Indeed 1C is now BETA's most frequent opening bid - besides PASS! Indeed frequency of all BETA openings are as follows % wise:-:

PASS>1C>1D>1H>1S>1N> {2C,2D,2Ma,2N,3C,3D}> pre-empts

This makes BETA the only system to conform to the mathematical "theory of information: Fisher 1903" as can be applied to discrete systems like our bridge bidding lanquage.

Interesting too is that when a suit is directly rebid - its always  promises 6+ cards! we do not rebid a 5 card suit. No bidding ambiguity in suit length. Sequences give definite suit lengths of 4 or 5 or 6 card suits.

BETA also champions cue-bidding and a cue bid at the 3-level can in fact be made implicitly agreeing partner's suit simultaneously! Also once cue-bidding starts BLACKWOOD is NOT used: 4N becomes TURBO and cue-bidding can continue if required into the 5-level at least.

Conclusion  BETA has now evolved  far from ACOL! indeed BETA lies closer to 5 card Major systems than to ACOL. BETA  is a fully fledged system in its own right.
We call it BETA now (pronounced 'better'). BETA is a strongly integrated syetem using a number standard conventions - some from yesteryear! The reader is strongly advised to take BETA as a whole -  making modifications is not wise given its intense level of  integration. Taking a part such as our 2C sequences or our CUE-BIDDING/TURBO one could adopt separately.

Beta has also adopted a number of important conventions, some slightly modified & others in limited ways:
NP Stayman (adjusted), Transfers (extensibly used to get a contract played by the most appropriate hand), BARON, SWISS, CROWHURST, RUBINSOHL(largely), TRUSCOTT (in concept in other cicumstances),  TRAP, TURBO with cue-bidding, MULTI 2D, DGR sequences, CDH, PUPPET(full), Splinters(limited) - NOT allowed responding to a 1-level opening bid - but can be used over a responder's bid.

Not to leave-out some other BETA basics::-
Change of suit in principle forcing on partner & responding with a new suit(cue-bid) at the 3+-level is a game force or also possibly with slam intentions.
Rebidding a suit by responder is WEAK and 6+ cards.
Jump rebids by opener announce a short suit with controls in a strong single-suited  hand ONLY when not announcing a 5-5+ hand. 
Cue-bidding is encouraged & coupled with a TURBO 4NT. A Blackwood 4N is NOT to be used after any cue-bid - 4NT is then strictly TURBO!
In 2C sequences 4N actually asks a King count! in 5-5 sequences 4NT is still in discussion but likely to be an inquiry.
Gerber has no seat in BETA!

BETA Curiously has 5 different meanings for 4N each easily distinquished by context!

Alertable artificial opening bids are 1C!: 2+ cards; 1N: 7+ minor cards 12-14 adjusted & no singleton, 2D!: Multi 3-way; 2C!: virtual game force; 2Ma! NF: 5+-|4 & <=5LTC; 3mi! 5-5+ 2 suited hands.
Alertable o'calls: 2N H+L, cue-bid 2 Highest, 1N Multi: 2 lowest or minor pre-empt or other 3 suits

Coming from 4|5 card Major systems?

If you stick to your strong NT, its not recommended, the move would not be easier coming from ACOL either BETA constrains the bid!
The 1 of a minor sequences have a strong parallelism in Beta that will need to be mastered.

READ THE INTRODUCTIONS before getting into the detail. Understand the 1C sequences first of all.
1D follow 1C sequences are mirrored in many ways - these are best learned simultaneously.
1H & 1S sequences are important and largely the same EXCEPT for when 1H is 4-4 in Majors.
Otherwise sequences opening 1N, 2C, 2D, 2Ma, 3mi have distinctly different handling and can only be learnt separately.
Defensive bidding is a separate learning - extensive and important.

Many conventions are used these can be studied separately: See section Conventions