akwoo

I think, on the contrary, we already see in this example how simple things can go wrong. Let's say your father gets a bunch of jobs in Two Harbors (well, today's Two Harbors - it's now a nice tourist town on Lake Superior). Enough jobs, with enough of a consistent clientele, that it makes sense for him to buy a house and maybe set up a small office in it instead of renting all the time. Two Harbors is a nice place, so you start visiting it on the weekend. When can it not be deducted any more? What if it turns out to be a really nice million dollar house on the lake? You see the difficulty. You could just say it should be left to common sense, perhaps as determined by a court, but rich folks can hire very persuasive lawyers. Simple rules inevitably have loopholes. Rich people hire folks who figure out the loopholes. You try patching up the simple idea to close the loophole, and they find more loopholes.

Partner has a full count of the hand and should duck the KC. Now dummy is cut off and, after hearts are cleared, partner can lead a low spade, endplaying declarer into leading from Kx.

I agree with your analysis of the situation. However, I want to know what's known about opener's propensity to open 1N with a 5 card major. If partner knows opener can't have a 5 card major, then you are already marked with the TH, so you should just lead JC and preserve partner's heart exit. (Note you won't stay on lead if you lead TH!) There's actually an ethical question about whether you can ask in this situation. (But, assuming the analysis is correct, and I think it is, I'm wondering why partner didn't lead their singleton diamond.)

As far as I can tell, most of the pairs I know who want something fairly complicated are playing the 30-year-old Berkowicz-Cohen structure, with 2♦ an asking bid with a variety of artificial responses all with artificial followups. It's not a full relay system, but it comes close. It has to be pretty good if it's that complicated and survived 30 years. I don't remember the details off the top of my head.

I don't think bidding is terrible at MPs - switch my majors and I'd bid. But I'm passing.

At IMPs, I lead a spade. At MPs, it depends on partnership agreement, which I hope is optimized to partner. Opposite a good player who can look at the dummy, recall the bidding, think about the problems I might have had and the problems declaring is having, I'll lead a low diamond. (It's the 5 in all my current partnerships, but someone could twist my arm into playing 3rd/low even at NT.) Opposite a partner who is likely to just return the suit if you lead a low-ish card, or who might think a little bit but not really figure things out, I'll lead the 8; in such a partnership we're also likely to have the agreement that the T is not an honor for "4th best promises an honor" purposes. Opposite a partner who is just going to return my opening lead no matter what, I lead a spade.

First of all - I'm bidding 2H only if it's forcing AND ARTIFICIAL. If partner bids 3N, I pass. If partner bids a natural 3H over an artificial 2H, I bid 3N.

Yes - 2H 3rd suit forcing would be nice, but absent that gadget, I'm bidding 3C. I'm still guessing if partner then bids 3S (I'll go for 4D), but at MPs I want to give partner a chance to get to 3N.

This really depends on system and partnership agreement. I wouldn't want to open this with a relatively unknown partner playing 2/1, but this is a not even borderline opening hand for most Precision partnerships. Playing that 1X-2Y-2X is nonforcing gives you more latitude to open this hand.

In Std Am or 2/1, with the 6-4 hand, you rebid the 6 card suit first with a minimum opener and the 4 card suit first with a stronger hand, the reason being that, if your partner does take a second bid, you can play in 3 of the second suit in the first sequence but not the second. This is a minimum opener, so 2H. But I don't know how it works with 4 card majors.

In a weak field, the folks holding your cards are passing 4♥, in which case doubling 5♥ is a nullo play - you already had a top if it goes down whether you double or not, but if it makes, doubling takes you from average to bottom.

I think it's worth saying something about how to think about this hand. Let's suppose partner has 0 high card points. They're still likely to have a club or two and a diamond or two, especially given the opponents have lots of hearts. How many tricks do you expect to take in clubs? It looks like you'll lose one club, two diamonds, and a heart, so you'll make 9 tricks in clubs. If you're doubled, that's -300. Now remember partner does have a decent hand, high card wise. How many tricks can partner take in a heart contract without being able to take any in a club contract? They could have ♠AK and ♥KQ at most, and that would be only 3 tricks, and it would require the perfect holding from them. You're still possibly taking no tricks in defense opposite that, for -420. Give partner the best holding for defense and worst holding for offense possible, and you're still quite possibly (though not definitely) better off bidding 5♣. (For the rest of you - yes I do have to do this thinking at the table - it's not automatic.)

This isn't one I want to put a lot of work or memory in - I think in all my partnerships it's weak.

I think, for learning purposes, it's best to always be giving honest count. On defense, you should be trying to count out the hand, every hand, and thinking about how to use the count information. Getting honest count from partner gives you more chances to practice keeping track of the count, thinking about it, and using it to figure out what to do. Yes it sometimes helps declarer more than your partner. It's not always easy to see when a count signal could actually help partner though (for one thing having the count in one suit helps them infer the count in another suit), and it only takes one wrong count signal at the wrong time to get discouraged about the discipline of counting everything out. Plus you generally have to learn how to tell the truth before you can learn when to lie.

Or 14(53) or even a very good in context 13(54)