The h3 option in 5. Nxf7

What could be some possible responses to this move in the main line for white?

5. Nxf7 Bxf2+ 6. Kf1 Qe7 7. Nxh8 d5  8. exd5 Nd4  9. d6 (this move is optional, it's just the line I play to block the diagonal) cxd6 10. h3...

h3 instead of... c3 because white knows that black is planning Bg4, and if black gets it off, white's usually hopeless.  The queen gets ejected from where it needs to be.  I think things would continue like..

10. h3 Bh4  11. c3 Nf5 (or is there a better option?)

Question now is, can white repel the attack?

This would be under the 9.d6 cxd6 section.

Here is my post on the above line.

11.c3 Nf5 12.Kg1 d5 13.Bb3 e4 14.Qe2 Ng3 15.Qf2 Bd7 16.a4 Nf5 17.Qe2 0-0-0 (17…Ng3 18.Qf2 is draw by repetition) 18.g4 Qc5+ 19.Kg2 Ng3 20.Qe3 Qxe3 21.dxe3 Nxh1 22.Nf7 Rf8 23.Nd6+ Kc7 24.Nb5+ Bxb5 25.axb5 Nf2 and white is fighting for a draw.

11.c3 Nf5 12.Kg1 d5 13.Be2 Ne4 14.g4 Qc5+ 15.d4 exd4 16.b4 Qb6 17.Bb5+ Kf8 18.Kg2 dxc3 19.Rf1 Qxb5 20.Na3 c2 21.Qxc2 Qxb4 22.gxf5 Kg8 23.Qd3 and I think white has a considerable advantage.  Computer still thinks black has a slight advantage.  This looks like the best play by both sides though.  Maybe someone might find something else?

Take a look at my above post.

Here's another line of this I analyzed out to get draw with what seems to be most or all of the best moves for both sides:

Similar situation to a lot of the Nxf7 lines: white forces black to make a move that causes perpetual, and if white doesn't he'll lose, but if black doesn't follow through and makes a different move he'll also lose.

Probably been found already.  I just happened upon it earlier

11.d4 e4! 12.Bd2 Bd7 13.Na3 0-0-0 is probably =+

Regrds

In that case, we have to reevaluate line G in the moves other than 9.d6 section.  That looks really good.  Now I cannot tell the better of the two moves 9...Bg3 and 9...Bh4.

Well old analyse not very good, unclear

mirage's 11.-Bd7 is simple and better 12.g4 and now 12.-Nd6 is interesting but complicate