Part of the confusion is using "NMF" as checkback.
Because when the auction goes 1C - 1D - 2NT, there isn't a "new minor" available.
1D is responded for a reason ( below is from Max Hardy ) :
a) tends to deny a 4cd Major ; if there is a 4cd Major, it means longer D and
opening hand ( game force )
values as well ( Barton's "Walshish" ) ;
b) a 2-suited hand only if the 2nd suit is Clubs;
c) a minimum hand which Responder feels is not compelling enough to bid 1NT;
or d) a hand primarily one-suited in D.
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I propose the following Structure based on the above and Barton's viewpoint:
1C - 1D ( Diam are bid for a reason over 1C )
2NT - ??
pass ( c ) and ( d ) if minimum
3C ( b ) 4+c and longer Diam, GF, 7+ hcp
3D ( d ) just long Diam, GF
3H ( a ) 4h and longer Diam, GF
3S ( a ) 4s " " " "
4C [ I would reserve as Gerber ]
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