[32519]

In spite of the fact that Muiderberg says 5M4m I have yet to meet anyone who actually plays that. Without acknowledging it, they upgrade the 4m hand to 5m. Why? If you can't stand a 5-1 or 5-0 split in the major on level 2, very few would be willing to play in a 4-3 fit in the minor suit on level 3. Opener has already conveyed a minimum hand. Responder can't stand the major. To try and rescue in a 4-3 fit inevitably is just asking for more trouble on level 3. So what do they do? The minor suit is upgraded to 5 as well.

[manudude03]

The thing about 4-3 fits after Muiderberg is that the hand with 3 trumps is probably doing the ruffing, so you usually get out for something respectable if not making. It's not an upgrade to 5 by any means. The danger hand is when responder is something like 1624 after a muiderberg 2S where you really might not have anywhere to go.

[gwnn]

You are quite wrong about whether these people exist - I meet them daily in the Netherlands. Still, I (gasp! horror!) actually agree with your point. It is a little bit silly to open Muiderberg with 5M4m... Of course it does lend some safety, for example if partner has 1543/1534 he can run to the 4-3 fit or even to the 4-4 fit. But I prefer to use it only as 5-5 when vulnerable, and I prefer not to use it at all if possible. It is one of the few things I don't like about the Netherlands, and that is saying something (I have no qualms with Dutch weather or cuisine, to give you an idea).

[helene_t]

Netherlands is a bit of the land of secretary birds so you will get lynched if you disclose your 5-5 agreement as Muiderberg. It must be exactly 5 in the major and 4-8 in the minor. Sometimes people will call it Muiderzand, Modderheuvel etc because they are afraid of running into troubles with opps or directors with idiosyncratic ideas about what exactly "Muiderberg" is supposed to mean.

[PhilKing]

Anyway, it's an English invention. It was certainly around at the YC when I first played there in 1983, and was known as Woo Two's. My guess is it dates from the mid seventies. It became licensed as Lucas Twos in the days when the convention tended to bear the name of the person who applied. 4-4 was even possible on a Friday night, and I suspect even 4333 in the hands of it's creator ...

[gwnn]

 helene_t, on 2013-July-08, 04:37, said:

Netherlands is a bit of the land of secretary birds so you will get lynched if you disclose your 5-5 agreement as Muiderberg. It must be exactly 5 in the major and 4-8 in the minor. Sometimes people will call it Muiderzand, Modderheuvel etc because they are afraid of running into troubles with opps or directors with idiosyncratic ideas about what exactly "Muiderberg" is supposed to mean.

We play it exactly as Helene described it above but my partner is still reluctant to call it Muiderberg outside the club as he claims there are people who think that term is reserved for exactly 5 in the major and exactly 4 in the minor.

[Zelandakh]

Lucas is different from Woo/Muiderberg Phil, since it can include both majors. The only difference between Woo and Muiderberg as I understand them is that Muiderberg is strictly 5 cards in the major, while Woo would allow you to open 2M with, say, 6M-5m. Chris Ryall talks about some of this in his Muiderberg entry.

[barmar]

 manudude03, on 2013-July-08, 04:26, said:

The thing about 4-3 fits after Muiderberg is that the hand with 3 trumps is probably doing the ruffing, so you usually get out for something respectable if not making.

What is he ruffing with the short hand? If he pulled, he must be short in opener's 5-card major. Meanwhile, opener will have to ruff the other two suits with his 4-card minor. So unless responder has the side suits well controlled, a forcing defense can easily make you lose control.

Then again, if it's that bad, the opponents probably have a making contract, possibly a game.

[32519]

 manudude03, on 2013-July-08, 04:26, said:

The thing about 4-3 fits after Muiderberg is that the hand with 3 trumps is probably doing the ruffing, so you usually get out for something respectable if not making. It's not an upgrade to 5 by any means. The danger hand is when responder is something like 1624 after a muiderberg 2S where you really might not have anywhere to go.

When the opponents smell blood they will throw you an anchor as a life-belt. They are not deaf. The player on lead starts off with a trump. If they hold the Ace of trumps, two trumps off the table are gone before you even get a sniff at trying to save your disastrous auction. Now declarer is down to two trumps in hand and you still have to deal with the aweful break in the major suit opened. If the opponents hold that Ace as well you get to trump nothing on the table. The life-belt you were thrown drags you down so fast that you end up drowning before you are able to cut yourself free.

5M4m Muiderberg has yet to be seen by me at the table.

[barmar]

Does anyone open 5-4 Muiderberg in 3rd seat? In 1st/2nd seat, you can hope that partner has enough strength to prevent that disastrous forcing defense. Once he's passed, it seems like suicide.

[hrothgar]

 barmar, on 2013-July-08, 10:48, said:

Does anyone open 5-4 Muiderberg in 3rd seat?

Yes

[gordontd]

 Zelandakh, on 2013-July-08, 05:34, said:

The only difference between Woo and Muiderberg as I understand them is that Muiderberg is strictly 5 cards in the major, while Woo would allow you to open 2M with, say, 6M-5m.

No, the Woos always describe it as "a major suit of exactly five cards..."

[manudude03]

 32519, on 2013-July-08, 10:42, said:

When the opponents smell blood they will throw you an anchor as a life-belt. They are not deaf. The player on lead starts off with a trump. If they hold the Ace of trumps, two trumps off the table are gone before you even get a sniff at trying to save your disastrous auction. Now declarer is down to two trumps in hand and you still have to deal with the aweful break in the major suit opened. If the opponents hold that Ace as well you get to trump nothing on the table. The life-belt you were thrown drags you down so fast that you end up drowning before you are able to cut yourself free.

5M4m Muiderberg has yet to be seen by me at the table.

It's a good thing the first lead is blind, nothing like finding a maybe 4-3 fit can just as easily be a 5-5 fit, now that trump lead isn't looking too hot. The other thing about 4-3 fits are they aren't even that easy to penalise, even when it is going down a fair few.

[32519]

 manudude03, on 2013-July-08, 18:18, said:

It's a good thing the first lead is blind, nothing like finding a maybe 4-3 fit can just as easily be a 5-5 fit, now that trump lead isn't looking too hot. The other thing about 4-3 fits are they aren't even that easy to penalise, even when it is going down a fair few.

No! No! No! By this you are agreeing that the Muiderberger's have upgraded the minor suit to 5.

[Zelandakh]

 gordontd, on 2013-July-08, 11:05, said:

No, the Woos always describe it as "a major suit of exactly five cards..."

I stand corrected. In that case I cannot see any difference between the two at all.

 32519, on 2013-July-08, 22:50, said:

No! No! No! By this you are agreeing that the Muiderberger's have upgraded the minor suit to 5.

It can be either - how does the player on OL know? The odds of not having an 8 card fit are relatively small. If the opps decided to play for such a misfit every time Responder took out into the minor, the Muiderberg pair would show a big plus. If the side suit is clubs, Responder is also usually declarer (2M - 3♣; P) so the misjudgement does not even show up immediately.

[Trinidad]

 32519, on 2013-July-08, 22:50, said:

No! No! No! By this you are agreeing that the Muiderberger's have upgraded the minor suit to 5.

?!?

Muiderberg is precisely 5M with a 4+ (plus!) minor. This means 4, 5, 6, 7 or 8 cards in the minor. (I admit that I would bid something else with an 8 card m and a 5 card M, but you get the picture.) Obviously, 4 is more likely than 5, but 5 or 6 is certainly possible.

So, when responder steers to a sign off in the minor, this could be a 4-3 fit or a 5-5+ fit.

BTW: To answer your original question about at least 5-5 and not 5-4: In The Netherlands (where Muiderberg is immensely popular) the disclosure problem is that people sometimes open Muiderberg with 5332 hands (making it 5M-3+m). Limiting the Muiderberg to 5-5 hands is considered extremely whimpy over here.

Rik

[helene_t]

 barmar, on 2013-July-08, 10:48, said:

Does anyone open 5-4 Muiderberg in 3rd seat? In 1st/2nd seat, you can hope that partner has enough strength to prevent that disastrous forcing defense. Once he's passed, it seems like suicide.

Almost everyone applies the same shape criteria in all seats, if anything a 4-4 or 5-3 is more likely in 3rd seat when white. There are some who require 5-5 when vulnerable but it's quite rare.

If you open 2M in third seat and catch partner with a singleton M, he will almost certainly have at least 8 cards in the minors since he didn't open a muiderberg himself. And since he doesn't need 2NT as a GF relay, he can bid 2NT with 45 or 44 minors. Which frees 3♣ which can be played as natural. I am not sure if it is better to play it as six clubs or as 3-5, but in any case your chances of scrambling to your best fit are decent as long as you have discussed these things with p.

[SimonFa]

 helene_t, on 2013-July-08, 04:37, said:

Netherlands is a bit of the land of secretary birds so you will get lynched if you disclose your 5-5 agreement as Muiderberg. It must be exactly 5 in the major and 4-8 in the minor. Sometimes people will call it Muiderzand, Modderheuvel etc because they are afraid of running into troubles with opps or directors with idiosyncratic ideas about what exactly "Muiderberg" is supposed to mean.

Aren't you supposed to describe the meaning rather than just saying "[convention name]" to protect yourself from these kinds of problems?

Also, given there is so much confusion isn't there some onus on the asking player to ask for clarification to protect themselves?

[helene_t]

 SimonFa, on 2013-July-09, 05:20, said:

Aren't you supposed to describe the meaning rather than just saying "[convention name]" to protect yourself from these kinds of problems?

Also, given there is so much confusion isn't there some onus on the asking player to ask for clarification to protect themselves?

Yes I agree with that. If the CC says "4-6M, 3+m, 0-12 points" it adds nothing but confusion to also state that "by the way we call this convention Modderheuvel".

A more problematic issue is that those pairs in fact play a fairly standard muiderberg style so it would be more in the interest of full disclosure to say 5M, 4+m, 5-10 HCPs. Kinda similar to alert the 1NT opening, saying "14-18 any shape" just to make sure not be ruled against in the unlikely event that p produced a 1NT opening with a 4441 shape.

[Trinidad]

The point is that the Dutch WeKo ("Laws commission") has ruled that "Muiderberg" is a term that can be used to explain (just like "Stayman" can be used) a weak bid with precisely five in the opened major and at least 4 in a side minor. The only thing is that if you explain a bid as Muiderberg and it turns out to have the wrong shape, the TD is supposed to assume that this was not the first time and that there is a CPU. That is the reason why some people call the convention "Muiderheuvel" ("berg" means mountain and "heuvel" means hill). It means: "We play Muiderberg, but sometimes we are naughty and we don't have a four card minor but a 5332 pattern."

Of course this should be explained properly, but most players will know more accurately what someone plays with the explanation "Muiderheuvel" then with "weak, exactly 5M, 3+ minor, not 4OM".

Rik