Frelling is a variant of the Assumed Fit preempting style The following system notes were sent into the Weak Two Archive by Richard Willey, correspondent of rec.games.bridge They are published as received with minimal editing to transform to HTML format.
The "Frelling" Two Bid preemptive structure is a comprehensive implementation of the "assumed fit" preemptive style initially developed and popularized by Bjørn Ekren. Standard preemptive styles used in North America are based on the assumption that a single suited hand pattern is required to provide weak hands with adequate playing strength. Ekren recognized that a two level opening bid promising four or more cards in two suits will typically allow the partnership to scramble to playable fit at the two level. Accordingly, Ekren developed a preemptive 2D opening promising 4+ cards in both majors that is often based on a balanced 4432 hand pattern. The Ekrens assumed fit preemptive style is becoming increasingly popular outside of North America. Being able to open the highly frequent 44xx and 54xx hand patterns at the two level with a LAW protected bid can be an extremely powerful preemptive weapon.
The development of the Frelling Two bid opening structure was based on a number of explicit design goals. First: I wanted to adopt a system of natural and non-forcing opening bids. Non-forcing bids put much more pressure on the opponents due to the high likelihood that responder will pass the opening bid. Adopting a natural preemptive structure forces Left Hand Opponent to use his limited bidding space to describe many more types of hands. Correspondingly, significantly more pressure is place on the opponents' overcall structure.
Note that Ekren's original 2
opening bid has some significant
constructive advantages. Most notably after the auction 2
- (x), responder can use pass to show a Heart preference with Spade tolerance
and xx to show a Spade preference with Heart tolerance. For example, after
2 - (x), pass holding 2344 shape. This improves the chance
that the partnership can scramble to their best fit. However, I believe that it
is better to maximize the pressure with the initial opening bid.
Second: the two diamond, two heart, and two spade openings should be very frequent.
Traditional preemptive styles in which two level opening bids show a single suited
hand with 6322 or 6331 shapes are certainly useful when you are dealt the
appropriate hand pattern. However, in comparison the Frelling 2
opening occurs five times as often as a traditional single suited preempt. The Frelling
2 opening occurs almost nine times as often.
Third: any preemptive opening structure needs to be safe. The preemptive opening structure should not leave our partnership unduly exposed to penalty oriented methods. The preemptive methods must allow partner to scramble to a safe fit on most hands. However, we accept that our partnership will be dealt the occasional hand that is poorly suited for these methods.
Finally: the preemptive structure should be constructive. Applying these methods against strong opponents with well prepared defenses should lead to a positive expected score.
| Shape | |
4+ Diamonds and 4+ cards in either major
Could be 4432, but not 5440 or 4441 |
| Restrictions | |
Requires at least Qxxx or any xxxxx in a major |
| Shape | |
4+ Hearts and 4+ Spades) or (4+ Hearts and 5+ Clubs)
Could be 4432, but not 5440 or 4441 |
| Restrictions | |
Requires at least Qxxx or xxxxx in either major |
| Shape | |
6+ Spades (6322, 6331, or 7222 shape)
or 4+ Spades and 5+ Clubs (not 5440) |
| Restrictions | |
Requires at least Qxxx or xxxxx Spades |
A series of Monte-Carlo simulations was used to evaluate this preemptive opening structure against the design criteria. The first simulation measured the relative frequency of the suggested opening structure compared to a traditional opening style in which two level preempts show single suited hands with 6322 or 6331 shape. For the purpose of this simulation issues such as strength range or suit quality were ignored. The only consideration was what percentage of hands had the appropriate shape for the opening bids.
Individual players might have very different ideas regarding suit quality restrictions for the various opening bids. It seemed most accurate to eliminate suit quality requirements altogether during the initial simulations.
Traditional weak 2/
| 2.3% | |
|
Suggested 2 Opening | | 19.2% |
|
Suggested 2 Opening | 13.1% | |
|
Suggested 2 Opening | 5.7% |
The second simulation measured the safety of the preemptive opening style.
Our goal was to simulate the frequency with which a preemptor would be able
to successfully scramble to an eight+ card fit opposite a 2
or 2 opening compared to players using traditional preemptive
methods. Responder will scramble whenever his diamond length is less than or
equal to his length in each major.
The percentage chance that the partnership will successful scramble to an 8+ card fit can be modeled as the percentage chance that [responder does not scramble and the partnership has an 8+ card diamond fit] plus [the percentage chance that responder does scramble, opener's hearts are greater than his spades, and the partnership has an 8+ card hearts fit] plus [the percentage chance that responder does scramble, opener's spades are greater than his hearts, and the partnership has an 8+ card spade fit].
Simulations show that following a two diamond opening, the partnership will be able to scramble to an 8+ card fit at the two level approximately 64.6% of the time. A similar analysis was performed for the two heart opening and found that the partnership is able to scramble to an eight card fit in Hearts, Spades, or Clubs 66.4% of the time. Both opening bids will identify a seven+ card fit 90% of the time. In this case, the more traditional preemptive style does come out ahead. Opposite a single suited preempt showing 6322 or 6331 hand type, the partnership will have an 8+ card fit in the bid major on about 76.4% of all hands. However, as an interesting point of comparison, "aggressive" players in the North America are frequently including 5332 or 54xx hand patterns inside their 2M opening bids. A 2M opening based on a 54xx or 5332 hand pattern will hit an eight card fit in the bid major approximately 54.3% of the time. Players who are interested in adopting a more aggressive preemptive structure might find assumed fit methods to be a safe alternative to highly undisciplined single suited preempts.
The last important question that needs to be considered is whether these preempts
will typically allow the partnership to achieve a positive score against strong
opponents using effective counter measures. My own experience with these opening
bids suggests that there is a distinct relationship between the strength range
shown by the opening and the partnerships expected result. These bids are much
more effective when they are anchored by a light opening system such as MOSCITO
then when used in conjunction with a very sound opening style. There are two main
reasons that explain this observation. First, while the 2
and 2 opening bids are highly obstructive to the opponents,
they also impede the ability of our own partnership to exchange information.
Delicate slam explorations can be difficult following one of these openings.
The weaker the strength range of the opening preempt, the less likely that
responder will have a hand that is strong enough to require a delicate slam
inquiry. The response structure can be better optimized if the focus is
restricted to part score and game decisions.
Second, the weaker the strength range shown by the opening bid, the more likely that responder will pass the preemptive opening holding a "strong" hand. In turn, this puts much more pressure on the opponent sitting in the balancing position. Simply put, when an opponent is judging whether to balance, a weaker range for the opening bid leaves more HCP strength unaccounted for. This in turn provides more opportunities for the opponents to guess wrong, and increases the opportunity to extract a good result opposite a bad balancing decision.
We suggest a basic response for use over the different opening bids.
A number of explicit design criteria were used when creating the response
structure. In discussing the design criteria, I will use the
2 for my examples, however, the same basic structure
is used over the 2 opening bid.
opposite any maximum hand holding 4+ Hearts without bypassing
3 in the case that opener held Spades. In a
similar fashion, responder should be able to invite 4
opposite a maximum hand with 4+ Spades without bypassing 3
opposite any hand with Hearts.
opposite any minimum hand and
3NT opposite most maximums.
response should be used to show Spades while denying Heart or Diamond tolerance.
If 2 is based on a 5 card suit it often results in a
suboptimal contract. If 2 is based on a 6 card suit, the
frequency is too low. If 2 shows a misfit with Spades and
Clubs it inevitably draws a penalty double.
3
3
3= Asking bid: Opener will clarify his heart holding and range
4
4
4
3NT = 5 Hearts and a maximum hand
3
3
3
3
3
2NT = Relay for Shape/Range
3NT = 6 Spades and a maximum
3
3
3
3
2
3
3
3
4
4
4
4
3NT = 5 Spades and a maximum hand
3
3
Pass = Any hand with Hearts
3
2
Specific auctions for a number of different hand types will be used to show how the suggested response structure fulfills the design criteria.
Hand type 1: Responder wants to invite game if opener holds a maximum
hand with 4+ Hearts. Responder wants to play in 3
Auction: 2
Opener will rebid 3
Opener will rebid 3N+ with Hearts and a maximum
Hand type 2: Responder wants to invite game if opener holds a maximum hand with 4+ Spades.
Responder wants to play in 3
Auction: 2
Opener will rebid 3
Hand type 3: Responder holds a game invitational hand with 4+ cards in both majors.
Responder wants to invite game if opener has a maximum hand.
Auction: 2
responder will bid 3
Hand type 4: Responder wants to invite 3NT if responder has a maximum hand.
Responder is willing to play 3
Auction: 2
Opener will rebid 3
Opener other rebids will show maximum hands and indicate responder's major and their length.
(After the auction 2
Hand type 5: Responder holds a single suited hand with Hearts and game invitational strength
Auction: 2
Hand type 6: Responder holds a single suited hand with Spades and game invitational strength
Auction: 2
After a 3
{Some players may prefer to treat this auction as showing a single suited hand
with clubs and game invitational values. Opener will rebid 3NT with a suitable maximum}
Hand type 8: Responder wants to drop dead in Diamonds
Auction 2
Hand type 9: Responder wants to drop dead in Hearts
Auction 2
Responder will rebid 3
(Alternatively, responder might want to start with a 3
intending to rebid 3
Hand type 10: Responder wants to drop dead in Spades
Auction 2
3
3
3
4
4
4
3NT = 4-5 Spades and a maximum hand
3
3
3
3NT = 5+ Spades and a maximum
3
3
3
2NT = Puppet to 3
3
3
4
4
4
3NT = 5 Hearts and a maximum hand
3
3
Pass = to play
2
3
Forces 4
Invites 4
3
3
3
2NT = Asking bid
4
4
4
4
3NT = Maximum hand, 5-5 shape
3
3
3
3
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