Minorwood Success

Minorwood is a form of Blackwood used when trying to get to a minor suit slam. The main idea behind it is that most normal Blackwood responses would put you beyond 5 of your suit, so bidding blackwood at a lower lever would be helpful. I'm not sure how the textbooks say you should play this but my main partner and I have agreed that if we have agreed on a minor suit and we bid 4 of that minor, it is keycard blackwood. Last night, for the first time, we got to use this with some success. At least we knew what we were bidding, but still got to a bad 6NT contract, which happened to make.

AKJx
Q98
Axxx
AK

Tx
Kxxx
KQJTx
Qx

Our auction:
1D - 1S
1NT - 2D(1)
2H - 3D(2)
3H(3) - 4D(4)
4S(5) - 6NT

(1) 2 way NMF: artificial game-force
(2) sets diamonds as trump
(3) last try for 3NT (if patner has a club stopper)
(4) RKC for diamonds
(5) 1 or 4 keycards

I was hoping to get to 7D. I didn't need much from partner (xx, AKxx, KQxxx, xx would be enough for 7D to be a 90% make). Needless to say, 6NT didn't stand much chance. We would have to find the spade queen on side and find Ax of hearts to come to 12 winners: 3 spades, 2 hearts, 5 diamonds, 2 clubs. But luck was with us on this night and the slam came home.