Funny, I am working on the Tarrasch main line...and one thread appears at same time about GM William DVD and Tarrasch game in his website.

What do you think about this move in one main line on Tarrasch variation:

1.e4 e6 2.d4 d5 3.Nd2 Nf6 4.e5 Nfd7 5.Bd3 c5 6.c3 Nc6 7.Ne2 cxd4 8.cxd4  f6 9.exf6 Nxf6 10.oo Bd6 11.Nf3 Qc7 12.Bg5 oo 13.Bh4 Nh5 14.Qc2 h6 15.Bh7+ Kh8 16.Bg6 Rxf3 17.Bxh5

and now 17...Rf5!? questionning the Bh5 bishop (instead of the direct and common 17...Rf8) ?

Nota: 17...Bxh2+ is now given as dubious  Delgado-Rodriguez,Sao Paulo 2004 (Inf 94)

Idea is merely to ask White "what is your plan ? " after one sequence like: 18.Bg6 Rf8 19.Bg3 Bd7 

The f5 square is destination for rook, questionning Bh5 too, in the other line: 17...Bxh2?! 18.Kh1 Rf5 Navara-Stellwagen,Corus - Wijk aan Zee 2006 and  Pan-Zhukova,Xiapu 2005 and Ismagambetov-Kosyrev,St Petersburg 2006... but in this line Black is an exchange down