I would like to hear from all of you about this system agreement with my pard and hear suggestions
We play Precision, with variable NT, 10-12/14-16 and 2C opener may have 5c+4M.
So 1D can be either balanced, 13-15/11-13, or max 15 with 4+D (can be 4D+5C).
HOW DO WE PLAY XYZ/XYNT ?
We play XYZ/XYNT 2-way checkback, that is, after both of the following sequences:
1D:1H:1S
1D:1M:1NT
-2C is puppet to 2D; if responder rebids, it shows a generic invitational hand
-2D is artificial "normal GF"
-suit rebid is weak, to play
-3C is weak, with 6+ clubs, to play
-all jumps are picture jumps in slam-going hands.
ONE MORE IMPORTANT PIECE OF INFORMATION
After 1D:1M, opener tends to raise responder's major with 3+ card support (unless hand is NT oriented, e.g. 4333 and/or lots of quacks)
THE QUESTION
Suppose opener has the following hand and you open a 13-15 bal 1D:
KJxx- Kx- Axx- QJxx
Bidding (uncontested) goes:
1D:1M:
?
With my pard we have agreed that with a balanced hand, we rebid 1NT even holding 4 spades, to describe better the hand, and to rightside the contract when there is no spades fit.
It does help to have a clearer picture of opener's hand: nebulous diamond can be VERY nebulous, and knowing that a spades rebid is unbalanced vs 1NT rebid is balanced does help responder.
On the other hand we can lose the spade suit.
There are no headaches when responder has a rebid (XYZ does the job).
But occasionally it fares poorly when responder is weak and does have spades and we play 1NT instead of 2S.
I am asking you the following questions:
1) in your opinion/experience, how bad is this agreement ?
2) how much does it improve incorporating Reverse Flannery responses to 1D ? Reverse Flannery help in 54 M hands, but not in weak 44M hands where opener will bypass spades after the 1H response.
Please note that it is very important the fact that the opening is not a "SAYC-ish" better minor opening but a nebulous opening, so I'd appreciate especially responses by "big-clubbers" (and yes, I know I would not have this problem if I opened 4 card Majors, but so goes life
Thanks a lot !

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