peachy

Not "surely" at all. It is a club.

I misspoke. Should have read what I wrote LOL. That is what I meant.

4 spades and 6 clubs, signoff.

Responsive Dbl originally was after opponent opened, we overcalled, other opponent gave a single or double raise, now our Dbl is responsive, showing the other suits and also short (or xx at most) in their suit. Other scenarios are also called responsive nowadays, but all responsive doubles occur when our side is the overcallling side. A weak two overcall is not the same as a non-jump overcall, so the OP Dbl is up to agreements though my take on it without agreements would be penalty. Takeout certainly makes no sense since the jump overcaller doesn't have anything but spades under normal circumstances; also, if it is not penalty, then there is no penalty double even available in that auction because the weak-jump-overcaller is certainly not reopening the bidding to allow for Dbl to be left in. Anyway, this is my understanding and preferences, probably unnecessary babble. But I answer No to all four of the OP questions. No agreement, be it penalty, responsive, optional, cards, are unusual enough to require an Alert in jurisdictions where some doubles are alerted. Certainly not a pre-alert.

If bidding diamonds, I am puzzled by all the doublejumps to 3D when 2D is already a jump. I agree this is a bit strong for 2D (good six-carder, good opening hand) but jump to 3D is not solving the problem in this case. My choice is Dbl, then bid diamonds.

4S. It does not mean we necessarily will play in 4S but I should at least show partner the Kx whether he was on a path to diamond slam or to spade slam.

After two bidding opponents and a passing partner, I don't like 1NT natural anyway, and even if that were the method we play, I would not bid 1NT with this hand. Double shows spades at least, the flaw in the club length is acceptable.

In SAYC, yes. Not many who say they play SAYC are actually familiar enough with it. There are important inferences to be drawn from the simple auctions as Adam explained.

Not true. It is a matter of agreement, not an automatic part of 2/1. It is giving no headaches to play whatever major suit raise structures one chooses, none of them obstruct the system at all.

If these are truly "C" players, the normal (in my experience and observation over 33 years) reaction when something seems to be amiss, is for C-players to pass as soon as possible before anything worse happens... So South is not going anywhere.

If it can be determined what the BIT likely means, then there would be actions indicated by the BIT and some of those LAs would be ruled illegal. I don't see how it could be determined what the UI from this BIT is (other than the responder was probably unsure of what to bid) so opener is free to act as he pleases. However, if 3S is forcing, he should not be passing.

"Opponents silent" appears to be unlikely, but I guess it is possible.

Pass is the "normal" response. Maybe it didn't work this time but the majority of time it will be fine.

Originally, nothing about alerts or agreements, just 5-card majors and common sense. Later, you added what the actual agreements were and the facts about alerts. It changes the picture significantly and likely changes how respondents answer the OP poll where no such details were provided.

The facts in your subsequent post are quite different than in the OP.

Depends on wwhether we had agreement on what 3S means and whether we had agreed whether the meaning stays the same after a Dbl or not. If on unsure ground as to agreements, I bid 4D.

The TGRs webpage says : All WBF sanctioned system permitted. I don't know what "licensed system" would mean. Looking at the WBF system policy, it appears to me (but maybe I am wrong) that TGRs would be a Category 3 event a) because it is not a teams event and b ) because it is not one of the events described under Category 1 and Category 2.

I would assume penalty. In unclear /undiscussed situations, when the Dbl is behind the bid and it could be penalty, it "is" penalty.

The A/E forum has a quite a few posters whose content is nowhere near A/E. I have no solution how this could be fixed, except case by case and in private, no real need to publicly embarrass someone who has either an inflated ego or who honestly does not know what expert/advanced means. I support strict zero tolerance in B/I forum and more moderators to nip it all in the bud.

I read only the chart which says it is unalertable. http://www.acbl.org/play/alertchart.html Jumps to 2NT or any four-level or higher notrump bid that is unusual. But you are correct that the regulation text only gives two choices for the unusual while the chart simply says "unusual". Time to tighten up this definition as well. If the opinion is unwanted - whether correct by law or not - it is easy to perceive it as a lesson. Perception is all there is so I would be careful, not to give the impression I am giving a lesson to a stranger. Maybe the OP folks were friends.

Again, assuming ACBL. Unusual 2NT is not alertable. It can be "unusual" in any way, just not a "natural NT" (which is alertable). The bidder probably did not know the reg any better than you did. Also, you knew they were weak intermediates, ask and don't assume. The explanation was lacking and they should have said which suits they were showing. The lesson in the end about alerting was a) probably unwanted, and if so, wrong by ZT and b ) wrong in general because the Alert Regulation is clear in that 2NT is not alertable whatever its UNUSUAL meaning was.

Illegal to have a concealed partnership agreement. Unethical to play a method that one knows is ruled as not-allowed by the RA. Also, 1D showing 4+ spades is not an "all-purpose bid with 0+ diamonds" when it specifically shows 4+ spades. In response to mgoetze, no RA regulations are perfect and ACBL is not an exception. Their regs just happen to be the one of the best known, in English, readily accessible, and commonly criticized by people who don't play in ACBL.

A. Leave responder alone, opener does not know why responder bid 3S. If you have an agreement that 3S is a generic invite, you are on extremely thin ice and typically will fall into trouble.

A self-appointed despot and a derelict who has abandoned his TD duty to rule by the Laws.

Negative free bids are alertable in ACBL games. Ignorance (or, more likely, inexperience) about the alert regulation is not an excuse for lack of alert. Other than "no adjustment" since there was no damage, TD should have educated East about his self-alerting responsibility.