A Straightforward Plan?

I ended my previous post, GM Blitz Battle PGN, with an action:-

While assembling the file, I learned that all of the matches in the same round used the same start position at each time control. For example, the first chess960 games of the first round, with 5 minutes for each player (plus one second per move), used SP768 BBQRKNRN. Given that the players had advance notice of that start position, it might be instructive to examine their opening moves.

Of the eight players who started the knockout, three are veterans of the Mainz tournaments and have featured in previous posts on this blog:-

• A Nakamura Sac Attack (February 2011),
• Alas for GM Grischuk and for Chess960 (June 2011)
• Chess960 'as a Spectator's Sport' (May 2010; Aronian - Anand, 2007 Mainz)

SP768 is shown in the following diagram.

This is a start position (SP) that offers a relatively straightforward plan for the first moves of both players: play b3/c4 (b6/c5) to open the diagonals for the adjacent Bishops, develop the Knights to e3 & g3 (e6 & g6), castle O-O, then study the resulting position and make a new plan. Three of the games followed this basic plan:-

[White "Grischuk"] [Black "LevonAronian"]
1.c4 b6 2.b3 c5 3.Nhg3 Nhg6 4.Ne3 Ne6 5.Nd5 Nef4 6.Nxf4 Nxf4 7.Bxh7 Rh8 8.Qc2 Kf8 9.O-O-O d5 10.e3 Ne6

[White "FabianoCaruana"] [Black "LyonBeast"]
1.c4 c5 2.Nhg3 b6 3.b3 Nhg6 4.Ne3 e6 5.O-O Nf4 6.d4 N8g6 7.d5 O-O 8.Bc3 Rfe8 9.Qb2 exd5 10.Nxd5 Nxd5

[White "MagnusCarlsen"] [Black "TigranLPetrosyan"]
1.c4 c5 2.b3 b6 3.Nhg3 Nhg6 4.Ne3 Be5 5.Bxe5 Nxe5 6.O-O Nc6 7.Nef5 d6 8.d4 e6 9.d5 exf5 10.Bxf5 Qc7

GM Nakamura took a different route:-

[White "Hikaru"] [Black "GMharikrishna"]
1.d4 b5 2.c3 Nhg6 3.Nhg3 d5 4.Bd3 a6 5.a4 bxa4 6.Qc2 Bc6 7.e4 Nf4 8.exd5 Nxd3+ 9.Rxd3 Bxd5 10.c4 Bb7

I've commented on his unorthodox approach in previous posts, for example Nakamura's Chess960 Openings (August 2014) plus two follow-up posts: Nakamura's 1.g4/b4 and Nakamura's 1.h4/a4. In this latest example, he appears to have recognized the obvious plan, then found an alternate plan starting 1.d4, with different initial objectives. The move also interferes with Black's basic plan by rendering 1...c5 problematic. Is this just an example of 'Dare to be different' or is there a deeper opening principle here?