I played a game the other day where my opponent used the petroff, and my sixth move made him think for longer than perhaps it should have done. Afterwards, I tried to find the move in an openings database, and I couldn't! So I was wondering if anyone here has come across this move before.

From Game Explorer on this site (set to show Master games):

move	games	white wins / draw / black wins
6.Bd3	7,400	41.6% 35.3% 23.1%
6.Be2	93	25.8% 34.4% 39.8%
6.c4	42	35.7% 28.6% 35.7%
6.h3	40	27.5% 42.5% 30%
6.Bf4	33	21.2% 24.2% 54.5%
6.Nbd2	26	11.5% 53.8% 34.6%
6.Be3	16	31.3% 18.8% 50%
6.Ne5	12	33.3% 16.7% 50%
6.Nc3	8	50% 25% 25%
6.c3	3	33.3% 66.7%
6.Bb5	2	100%
6.Qe2	2	100%
6.a3	1	Volokitin Alexander - Christensen Jan (2002)

I haven't seen Nbd2 before either, can't see anything wrong with it, might be a bit slow but it certainly turned out well for you, your play from move 9 on was very good and a pretty finish :-) I'm not sure, particularly in the light of how play went, that Bg4 was the right idea from black since with the f3 knight protected you could in fact have been more aggressive with your white B.  Also he is not really threatening anything with it is he?  But you certainly took advantage beautifully, nice one.

Strange that, it didn't look all that bad, well played anyway man.

Wow, 13...f6 was an awful move from your opponent that allows you to set up a devastating windmill:

awesome moves good counter attack

16.... f6

17 Qd5+ Kh8

18 Nf7+ Kg8

19 Nh6+ Kh8

20 Qg8+ Rxg8

21 Nf7#

(Philidor's Mate)

Is this the Damiano variation?  I think black has several possibilities and 6...Bd6 is among the more successful.

 I have only heard that being called the Smothered Mate.

There are many "smothered mates", this particular pattern is Philidor's mate/ Philidor's Legacy:

http://en.wikipedia.org/wiki/Smothered_mate

It's also called Philidor's Legacy GM Alwayswin

Ahh -- even better.  My miss.

It's called the damiano variation huh? No wonder f6 was bad. Anyway 6...Bd6 does look better, and yes, Be2 was somewhat passive, although I'm still surprised that 6.Nbd2 seems to have such little success. But then, its not very common either, so who knows? It certainly surprised my opponent.

WOW!

ADK

Personally I think that black should simply retreat the knight with 6...Nf6, just leaving your knight slightly misplaced with an equal position. But as we saw in your game the surprise value - getting your opponent out of book and making him/her think - must be worth something.

Nice win.

Stuart