sound play in the ruy?

the idea being to crawl back into c2 the hole when the inevitable Bd7 is played via Ba4 and to further claims to the center, followed by a natural Nc3.

4.d4 is the mainline against the steinitz variation I believe.  4.c3 seems unnecessary. 

Hint: Game Explorer, http://www.chess.com/explorer/.

Seems a reasonable enough idea.  The Ba4-Bc2 part seems a bit time-wasting if you're not getting chased around by the Q-side pawns, but it does provide you the opportunity to recapture cxd4 after playing d4, which is nice.  I've never been fond of how the game simplifies quickly in the Steinitz variation, even if it does result in a plus for White -- maybe I'll give your idea a try next time the opportunity arises.

But in the deferred steinitz c3 should be played.

unnecessary? what about the strong center that will almost inevitably follow?

spiffe; good point( searches opening explorer). about the a4 stuff. rather than an unprotected bishop trade, you can hold on to the bishop pair, have them both pointing at the king, and only for one 'wasted' move.

southernman; only 5 games in the opening explorer with that move order( 60/ 40 white). Makes sense though- ridding white's central pawn and developing a piece at the same time.

c3 is a bit unnecessary because black doesn't want to give up the center with ...exd4 anyway, and this way d4 is easily played and the knight can now come to c3. In fact it's like the ideal "scotch game" for white.

"Church!"

I think c3 in these kinda king pawn positions is usually a decent move, and I see no reason why this is an exception. Especially if it gets your opponents out of book a bit.

If the mainline is d4 I'm not such a fan because I like to keep the depth of a reasonably closed position through the opening. d4 just seems like I'm playing some sort of Philidor with my bishop on b5 instead of c4.

Who wouldn't want to play a philidor as white, which is basically what comes out of 4 d4? In the scotch black gets alot of counterplay in the center with ...exd4, but here after ...d6 the bishop cannot help on c5 or b4, giving black a more passive game and white develops quickly. If white plays c3, he takes away c3 from the knight so black can simply not take there. However, with the move ...a6 thrown in, eventually if white tries to play d4 without c3 black can often play ...b5 and then put strong pressure on the center with ...exd4, because then if the c6 knight moves on a Nxd4 recapture black can play ...c5 then ...c4, trapping the bishop. This is the main reason why c3 is played when ...a6 is played. If d4 could be soundly played without this happening, c3 would in fact not be played because if black doesn't give up the center then white's development is slowed, but this is often the only way to play d4 in the mainlines.

But here white can immediately play d4, (black should have played ...a6 before ...d6) so c3 isn't really necessary and the knight will go to c3 instead of d2-f1-g3 which is more convenient.

d4 beats steins its all fiqured out already