Help Suit Game Try ("HSGT")

After bidding of 1-2 or 1-2, if opener has enough to invite game (16-18 points), and has a 3+ card side suit with just 1 of the top 3 honors, then instead of inviting by bidding 3 of the agreed suit, he can invite by bidding the other suit at the cheapest level, which asks responder if he has help in the suit, either a high honor or a singleton or void.

With such help, responder bids game; otherwise, he rebids 3 of the agreed major.

Since responder showed 6-9 points, the experts say (Google it) that HSGT should normally be used only when opener has 16-18 total points. If opener has more than 18, he should just bid game. If he has fewer than 16, he should pass.

Bobby Wolff said in his Dec. 16, 2021, column that a player should pass with J64 AKQT9 9832 A because of your outside points being of questionable value - an unsupported jack and a singleton ace. In his Feb. 18, 2022, column, Wolff says that with KQJT6-AKT4-Q75-5 opener should bid 3H with just 15 because of the concentration of values and that if partner has 3 spades and 4 hearts, he should raise to game in hearts so that any losing diamonds in partner's hand can be discarded on the long spades in order to ruff opener's diamonds.

In the Feb. 2019, Bridge Bulletin, p. 57, Marty Bergen says:  

Too many players believe that 4-4 fits are always the place to be.
I beg to differ. I much prefer 8-0, 7-1, 6-2, or 5-3.

In March 2017 Bridge Bulletin, p.58, with AK873 KQJ4 3 A54, the bid 3 is made, as is also the bid in Wolff's Aces column of 2-18-2022 with KQJT6 AKT4 Q75 5.

But in the Oct. 8, 2022 Aces column with AJ9832 K7 KJ852 -, Wolff says to just jump to game because not much is needed from partner and bidding 3 may help the opponents as much as your side.

Non-HSGT Bids by Opener:

If opener has 19+ points, he should just jump to game.

If opener invites with 3 (not in competition), it tends to indicate a weaker trump suit, such as Qxxxx rather than a need for help in a side suit (since HSGT was not bid). If responder had extra honors or extra length in the trump suit, then he should bid game; otherwise, pass.

In competition, bidding 3 of the agreed major shows a hand with extra length but not extra strength.

A rebid of 2NT shows something like a 5-3-3-2 hand with 16-18 HCP and scattered honors.