1. Dxb7+? Dxb7+ 2. Sxb7...
1. S~? flight (2. Dxb7+ Dxb7#) D~!  
However:
1. - Queen moves? 2. Sd7+! Dxd7 3. Dxb7+ Dxb7#
Sujet: reciprocal "Verharrungspflicht"...

Thematic try:
1. Lxd6? (2. Lxe5 [3. Lc7+] Dxd5 3. Sd7+ Kc6
4. b5+ Dxb5 5. Dxb7+) Lxd6!

1. Le7! thr. (2. Lg4 leaves diagonal g4/d7,
anticipatory unpinning black Queen, followed by
3. Da7+ Kc7 4. Sa6+ Kc8 5. Dxb7+ Dxb7#)
1. - Lf6 (2. - Lxe7!)
2. Lxd6! (3. Lc7+ Dxc7 4. Sd7+ Dxd7 5. Dxb7+)
Mainplay-defence:
2. - Ld8 → dresdnerisch! (3. - Lxc7)
3. Le2! Zugzwang! T~
Strukturkollaps...
4. Sa4+! Dxa4
5. Ta6+! Dxa6+
6. Da7+! Dxa7#

Brisant:
4. Tb5+? Dxb5 5. Sa4+/Sd7+
5. - Ka6!! → pinning own Queen...

2. - Le5
3. Lxe5! (4. Lc7+) Dxd5
4. Sa4+/Sd7+ Kc6
5. b5+! Dxb5 
6. Dxb7+.
That's  the reason, why 1. Lg4~ (2. Le7) is failing:
1. - Lf6! 2. Lxd6 Le5! 3. Lxe5 Dxd5! 4. Sa4+/Sd7+ Kc6
5. b5+ K(x)d7! 

....Weltspitze (Juror Dr. Klaus Wenda)