Finally, some discussion about chess, now that other people have become involved.
Firstly, my simple reason for staying away from 9...c5 - White does have open lines and a slight development edge, so I don't want to open the position. Not that I think white then gets enough, but why give him any play at all? 9...Nc6 just puts the knight back where it was originally and says "Okay, you've given me two pawns for an investment of my time - show me the mate."
I don't really know what to make of the lines after 9...c5 yet, other than to say that I still think black is better, but I think white is risking having some fun. I have no doubt that objectively 9...c5 may be strong, but it seems less simple to me.
With regards to the lines after 9...Nc6, which I am personally more interested and more invested in:
Firstly, I still propose 10...Bd7 to be a possibly correct move order, since after 11.Rd1 h6 we found 12.Qh4 to be incorrect and 12.Bh4 to also be insufficient, and therefore 12.Bf4 seemed the only try. As far as we could see there, white gets a pawn's worth of compensation, in rough terms, for two pawns' investment.
As for the line 10...h6 11.Qh4, I think black should try the move 11...Nh7!? - giving up castling is really not an issue for me when I can console myself with two pawns. Another set of pieces come off the board.
So, after 10...h6 11.Qh4 Nh7 (which gives a pawn back), white only has two tries that I can see:
a) 12.Bxe7 Qxe7 13.Bxh7 Qxh4 14.Nxh4 Rxh7 15.Nb5 Rb8 16.Nxc7+ Ke7 and black is a pawn up. White's a bit more active. But black is a pawn up, with a bishop vs knight, in a near-endgame. If this is the best white can do, he is busted.
b) Instead white can try to muddy the waters with 12.Qh5!? Bxg5 13.Bxh7! Bf6! 14.Ne4!? Qe7! (Though 14...Rxh7 15.Nfg5!? hg 16.Qxh7 Ke7 may also be good for black, it again overly complicates things, and my gut feeling is that white is fine after 17.Nxf6 gf 18.Qg7 with chances) where white has nothing better than 15.Nxf6+ gf 16.Be4 Bd7 intending to castle long. Black is two pawns up, with two pairs of pieces off the board, a fully developed position and even a semi-open g-file. White is busted.
So I maintain that after 9...Nc6 white has no line whatsoever which demonstrates adequate compensation for the material. After 9...c5 I reckon white could cling to =/+, whereas 9...Nc6 really seems between -/+ and -+. For two pawns white really needs clear compensation and a guaranteed lasting initiative into the endgame with good chanes of regaining his material. He doesn't appear to have either in the 9...Nc6 variation.
Incidentally, should 9...Nc6 catch on, since I have been analysing it for several years I would like the naming rights. Though I will not tell you right now what I would call it.