Gilithin

This will be treated as discussions regarding business in the House and not result in charges. Take the easy stuff, like DJT openly and clearly attempting to incite a coup, before going for grey areas like this.

3rd seat green I guess we are picking between 3 and 4. I suspect 4 is more likely to draw a good transfer than have the extra level of preemption be helpful, while 3 might just draw a heavy 3♠ from LHO. So I think 3 is probably the better option but I am not overly optimistic about winning this hand in the auction regardless of what we call. There might even be an argument that psyching a 1♥ opening is the best way of keeping them out of a good game but that obviously is risky as the extra space definitely will help them.

Yes, by choice I use an identical structure for Muiderberg 2♠ and for Multi-Landy: 2NT relay; 3♣ P/C; 3♦ INV+ with hearts; 3♥ good raise; 3♠ PRE.

Different structures are possible but it is usually played as an artificial relay, as in Chris Ryall's write-up from many years back.

There is a theory in system design circles that weak 2♠ and 2♦ openings are nearly always effective and a weak 2♥ opening generally less so. So a Muiderberg 2♥ opening is indeed much less effective than the Muiderberg 2♠ but then again the Weak 2♥ opening is much less effective than the Weak 2♠ and counter-intuitively also less effective than the Weak 2♦. For those that want to play both Multi and a "both majors" preempt, a relatively popular structure is 2♦ Weak 2M; 2♥ 4+♥4+♠; 2♠ 5♠4+m. Last time I checked, admittedly a while back now, this was more common than a true (2♦) Ekrens opening.

You bid 2NT (or 2♠) to get the hand out quickly rather than forcing to the 3 level with a second double. And if not prepared to play in 3♥, passing the second time around rather than doubling again makes more sense. It is quite a common theme in chapters on competitive bidding for writers to note that this specific auction (1X - 2Y) a particularly dangerous one is to get involved with and you already made most of the points as to why that might be so. It does vary a little by system - in Acol a pair might only have 18 rather than the 22 S+5 pairs might expect - but the principle of getting in and out as fast as possible remains for all of them, which is the main reason I mentioned 2♠/2NT as an alternative to doubling twice. If you disagree with this general principle, rather than just dismissing it for this particular hand, that might make for an interesting discussion.

The general meta rule for doubles is 1st shape, second strength, 3rd blood. Since you were happy to play at the 3 level, an alternative to the first double would have been whichever of 2♠ or 2NT your partnership uses for this hand type.

The German (and French) bidding methodology is somewhat different from other parts of the world and you have to be careful when making definitive posts based on it, particularly in the N/B forum. Germans love to jump over NMF, 4SF and other such bids; most others do not. There is nothing wrong with using a system that bids 2♥ rather than 3♥ with a maximum. If Responder has an invitational hand, they can ask min/max by the simple method of raising to 3 and sometimes the extra level of bidding can be useful. Similarly German and French players are taught never to rebid NT with a singleton or raise on Opener's rebid with 3 card support. That is fine within the context of those systems but the English speaking world (of which Australia still qualifies) mostly uses a somewhat different approach that aims to reach better contracts overall rather than looking better on paper. The truth is that both approaches have their merits so telling that one of them is "the book rebid" without further explanation is doing them a disservice. Back to the hand, your partner is in control after you choose 1NT so you now describe your hand as best you can. Whether that will be 2♥, 3♥ or something else depends on the system you are using. With a generic Aussie pick up partner playing some generic 5and strong system, I would choose 2♥. With GIB, I'll look through the meanings of the rebids and select accordingly.

Slightly surprised to hear this specifically from you - is it not the currently preferred style in Germany? The truth is that 1♦ - 1♥ -- 1♠ can be 4-4 in the vast majority of natural systems in the world, not necessarily as a Weak NT but almost always as a 4144.

The answer to this depends on how the pair plays X and 2NT. This is why the agreements are important. Without some basic agreements, competitive auctions can easily turn into more or less random guesses.

In order for us to make an informed decision over 3♥, we first have to know what agreements were in place for partner over 2♥. Once we get that far, we also have to discuss agreements for our seat. Many players, myself included, prefer some form of Thrump double at the 3 level. Meanwhile, many social players still play all doubles above 2♠ as penalty in line with Culbertson's rules. Looking at the South hand, it would also be helpful to know that we are playing against weak/social players. These all seem to be factors that might affect the choice here.

It seems that it also makes if declarer wins the first trick in hand intending to play on diamonds, then switches to a spade followed by the ♣Q when the bad split is revealed.

Neither - it is simply a fact that you are the best player regularly posting here. In any case, I am super-happy to have the same line (at least the first half) even if it turns out not to be succeeding. As with Paul's recent hand, I find it better to judge improvement in declarer play by how often I come close to the best players posting rather than what works on the actual hand. In this regard, BBF has always been a fantastic resource offering unrivalled insight into the way a few top players think.

Without any Leb agreement, 3♥ should show the same as 3♠ Rubensohl or a slow shows 3NT.

1♣ - 1♠ -- 1NT would be another possible start to the auction. Not that it matters. I suppose the obvious lines here would be to play for 3 diamond or 3 club tricks. The latter looks a bit easier to manage so I would probably start with ♥A, ♣Q without much conviction. I would assume we are looking for something much more exotic for the hand to find its way on to the forums though. Maybe this is one of those book hands where we have to cash all the hearts on the basis that the defence is subsequently endplayed. It does have a lot of the elements for that hand type so it's not completely out of the question but no way I am going to try and work that out at this time - maybe in the morning if Mike hasn't posted the solution by then...