1D opener
Enhanced Precision XYZ-forcing 2C by Responder
XYZ-forcing 2C by Responder on second bid at least invitational (with exceptions); less strong than 2D)
Note that the 1D-1H sequence is different than the 1D-1S sequence that follows...
o1D-1H-(1S/1N)-2C forcing to o2D
  rP= weak hand w 4+d
  r2H= 5+h, invitational (remember:1D-2H is preemptive with hearts and spades, 1D-1H-1N-2H is drop dead)
    oP- all minimal hands, all other bids natural
  r2S= 6+h with 5+sp invitational (remember: 1D-1H-1N-2S promises exactly 6h and 5sp, invitational)
    o2N= asking bid (we will never remember this!)
      r3C/3D= 2clubs/2diamonds or void club/void diamond, 2 of other???????? (NEEDS CLARIFICATION!)  
      r3H= 1club and 1diamond
      r3S= 5710 (void club)
      r3N= 5710 (void diamonds)
      r4C= 6700
??     r4H= 5800
  r2N= invitational to 3N (asking for spade stoppers if after 1D-1H-1N since might have stiff spade 1444)
  r3C/3D= invitational with 4 hearts and 5+ minor
  r3H= strong, not solid 6+ hearts, invitational
  r3S= solid 6+hearts, GF (all bids below this are invitational; this parallels the 3S response to 1C)
  r3N= weak 5+hearts, NF...."Pass or bid 4H please"
  r4C= key card gerber in clubs
  r4D= Gerber for NT
    0/3
    1/4
    2 weak
    2 strong
  r4H= mild slam try in hearts (remember: that 1D-1H-4H is sign off; going thru 2C is stronger)
    P= done
    All other bids= strength in that suit and slam interest (REALLY? TALK ABOUT THIS)
           
    After 1D-1S-1N-2C-2D
o1D-1S-1N-2C-2D
  r2H= 5 spades and 4 hearts (exactly), invitational
  r3H= 5 spades and 5 hearts (exactly) game force (if 5-5 inv, 1D-1H-1N-2D, asking about three card major)
  r4S= mild slam try since 1D-1S-4S would be sign off.