2.c3 isn't mentioned in the book at all, but 2...Nf6 already leaves white without a normal way to defend the e-pawn.
In the Pirc-like positions, White has a few ways to try to prove that black's queen's knight has come has come out too soon--I just don't find them very convincing.
Keep in mind that 1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Nf3 Bg7 5.Be2 O-O 6.O-O Nc6 is a viable sideline, and that after 6...Bg4 7.Be3, 7...Nc6 is the main move, so it is hard to argue that the Nc6 is fundamentally misplaced.
1.e4 Nc6 2.Nf3 d6 3.Bb5 Nf6 4.Nc3 g6 5.d4 a6 6.Bxc6 bxc6 7.O-O Bg7 offers white some development, but black has the bishop pair and the b-file. Black's extra c-pawn helps control the center and can usually reach c5 to challenge white.
1.e4 Nc6 2.Nf3 d6 3.d4 Nf6 4.Nc3 g6 5.d5 Nb8 6.h3 is a good try for white, who has space, but he is not yet actually ahead in development, and black will have play on the dark squares, weakened by 5.d5.
Of course, the resulting positions are not to everyone's taste. Not everyone is going to love playing 1...Nc6, but some will.
I have a question. After 1.e4 Nc6 2.Nf3 d6, how do you get any kind of normal Pirc position? The Knight is normally not committed to c6 this early, if at all. I played 3.Bb5 in my recent tournament game against this variation and had a winning position after eight moves against my 2100-rated opponent, although this was helped by his bad play in moves four through eight.
Also what do you play against 1.e4 Nc6 2.c3, for example? If you play 2...e5 you're back in an Open Game (Ponziani after 3.Nf3 or White can play 3.d4) and 2...d5 seems inconsistent with the rest of your repertoire, although perhaps justified here due to the White Knight's inability to use the c3-Square to harass the Queen...
Why should white be afraid of the classical pirc (with nf3 and h3)?
In anycase....I am reluctant to overtend so early in the opening, but what about 1.Nf3 Nc6 2.d4 d6 3.d5!?, looks very interesting, although its not best probably. I mean white can go for safer options.