Opening basics - space

On space principles, are the next two optimal moves d4 & Be3? 

Space also explains knights developing to the centre rather than sides - twice as much space!

If you are uncertain of the next move, is the one that leads to controlling more space the one to go for?

Is it space attacked in enemy territory that really counts, as I have read? So d4 attacks 4 squares, Nc3 "only" attacks 2 squares. Is that why d4 is *so* good?

As rooks can penetrate space down files, is it worth sacrificing a pawn for space? For example the B might take g2 pawn, then R attack it, drive it away, and be attacking four squares down the g file. How much space is a pawn worth?

Interesting subject.

space is quite important! i usually park my car outside to have more space in the garage for example

Indeed :)

I have created a second post explaining the basics of openings for intermediate players . Learn to place your pieces well in the opening with the second part of our opening principles:http://chesstrainerapp.blogspot.com/

That R threat on Q is interesting. I usually do Re1, but it seems a bit pointless  after the K castles. What's the best move for Black here? Nc6 and he gets forked. e5*e4 seems the only move, which damages his centre and white's move to e5 looks strong. 

I like playing that as well. One thing - it does seem to restrict white's space, with only the white B seeming to have much, and that's about to get attacked. What I'd really like to see is Grumly actually playing some games on chess.com, occupying space, and defeating some of you >2000 players . 

I must admit I prefer Reed's theory to all this space stuff: "develop your pieces and castle your king." Is there a GM pushing this space stuff or is it Grumley's "top of his head" guess?

I have written another article about how to manage time in the opening in my blog:

http://chesstrainerapp.blogspot.com/