Where does the Knight go? It depends, but after a3, it doesn't always go to Nbd2 as quickly as you suggest. And, as Tony notes, in the main lines its development is delayed and usually then is to c3.
MNb wrote on 12/11/09 at 01:53:28:
5.a3 f6 6.exf6 and 7.Nbd2
No, 6..Nxf6 7.e3 Bg4 8.Be2 and after a subsequent exd4, the Knight will come out on c3.
Quote: 5.a3 Nge7 6.Nbd2
No again, this is the main line, which runs 6.b4 Ng6 7.Bb2 a5 8.b5 Nce5 9.Nxe5 Nxe5 10.e3 Be6 11.Bxd4 Nxc4 12.Qc2 and again the Knight will come out on c3. See Topalov-Morozevich, Monte Carlo Amber (rpd) 2005 and the books by Avrukh, Schandorff and Davies.
Quote: 5.a3 Be6 6.Nbd2
Yes, this generally transposes to 5.Nbd2 Be6 6.a3.
Quote: 5.a3 Bg4 6.b4 Qd7 7.Nbd2
Here, actually, I would play 6.Nbd2, which is a direct transposition