Siegmund

You aren't the only one opening it 2C. I am happy to start with 2C-2D wait - 2H. (And if we are playing 2H immediate negative and partner responds 2H, I am indeed willing to drop him in it, but prepared for that to be the wrong decision.)

One more vote for Pass. Nothing else is remotely close IMO. mikeh does ask the more interesting question. Redoubling MIGHT be right, if partner has 4 diamonds, but I don't think there is much hope of a spade fit, and partner is gonna have a quality suit for a 2-level overcall at imps.

After 2H-Pass I like the simple direct 4H, and expect to be left in peace as often as not. If it had started 2H-Double I'd feel more like this was a "3 or 5" kind of auction. Now, if it goes 2H-pass-4H-4S and comes back to me, THAT is a harder question, but I take the push to 5H.

If they are playing exactly as described in Kennedy's book (p. 61), then yes they need to be alerting 1D (positive response denying 5-card major), 1H/1S (promising 5-card suits), and the weak jump shift responses. Sort of like an ancient ancestor of Montreal Relay.

Yes 3S sets trumps even opposite a void. With my reg p we'll be playing sweep cues: 2C-2D 3S-4C 5H (promising 1st and 2nd round of D, 1st and 2nd round of H, and the other club control, and good trumps) which will may alert p to the fact I care about the 3rd round of diamonds. Either he will show it, or he will GSF and I will show all three. Playing standard, I would start with the 4C cue, 4D cue, and on the next round probably cue 5D again, to call partner's attention once again to his DQ along with his aces and trumps.

Something to keep in mind is that one of the great things about game tries - the reason we use them and not just 1-2-3 mom and pop raises - in that we are telling partner "hey, your queens in these two suits are likely tricks, in the other two suits not so good; in light of that information, do you like your hand or not?" It's a different question than a cuebidding auction copes with. A sequence like the one OP posted means that asker was interested in a slam if answerer's queens were all working AND a few other good things came up. After answerer said, sorry, my minor honours are badly placed, asker didn't have slam interest anymore. I would NOT reinterpret the game try as a cuebid, if asker subsequently cuebids (in the context of aces-first cuebidding.) It's conceivable that if you freely cuebid kings, you could agree not to make HSGTs on suits without high honors. Shrug.

The Miles book had a really great exposition, I thought, of the times when it's appealing to be able to show a 4-card major as overcaller. The alternative to overcalling in the 4CM directly is to find another method of showing them: with my regular p, we gave up Michaels in favor of a convention to show 4-5 hands. Others adopted Equal Level Conversion to handle these hands. (That would be my 3rd choice among the three - but seems to be the most popular.)

awm's style points are important I think. My tendencies seem to be similar -- reverse flannery hands are only a problem after 1m-1S-2m, and rebidding 1NT more often (and also being a little bit looser in my reverses than is fashionable, down to say Kxx AQxx KQTxx x, counting extra for fitting SK+shortness) cuts way down on the need for that.

Why 3D and not 2NT? South will presumably raise to 3NT, and maybe north will invite with 4 and maybe not, but the bidding will def end at either 3NT or 4NT.

I voted natural constructive, since that's what I play with my regular partner (and an Ogust-like 2N rebid by opener), but I have no quarrel with strong Soloway jump or with fit-jump (with appropriate discussion about promised suit quality - my preference being KQxxx+), which I currently use only as a passed hand. Interesting to see so much love for reverse Flannery. It looks like a reasonable idea, but never yet had a partner ask me to play it.

Even playing support doubles I don't think I am doubling at my 2nd turn here. I will be happier passing at my 3rd turn after showing both my suits - and if I decide I am not happy passing at my 3rd turn I can at least have a cheap spade rebid available. (Actually with my regular p I have an agreement that a support double promises Qxx+, never xxx/Jxx. Sort of halfway between support and Rosenkranz.)