advanced repertoire with 1.d4

having done some more research with Rybka4, which in many cases
gives a better evaluation of some positions than eg. Rybka3,
another repertoire, which i use in my computerbook is emerging,
namely with 1.d4 .
Against e4, having done considerable analysis on many lines
and playing some testgames both on ICC and playchess.com,
the Sicilian 1..c5!, in particular Najdorf, (with d6 and a6)
looks quite a strong defence, currently even the strongest.
In fact these developments are not surprising, as many top
players also have switched their repertoire from e4 to d4, eg
world champion Anand. Although its often said that this is because
of the Petrov or the Marshall gambit defence in the Ruy Lopez,
for me the reason is the Najdorf, which in fact is played quite
often on playchess.com against e4. Highly accurate play is
required in this sharp, double-edged defence, so for average
players - and certainly beginners- i still advocate 1.e4
as most suitable repertoire.
By starting with 1.e4, you learn variations like the CaroKann
and the French, which knowledge a more advanced players can
still use in case of 1.d4, eg in case of 1.d4 c6?! 2. e4!
or 1.d4 e6?! 2. e4 ; another reason to start with e4,
and imho continue with it a long time, eg up to about 2000
or higher, is not only the difficulty of the Sicilian, in
particular the Najdorf, but also the simple fact that by
playing e4 a player usually will learn tactics, especially
opening tactics sooner than when playing the
*initially* more 'positional' 1.d4

Ofcourse i've updated my demo bookbuilder book (>500,000
positions) which you can download for free at:

http://shareit.com/product.html?productid=184868

(14 days trial, and you clearly can see after 1.e4
the Sicilian, .. c5 as preferred defence).
More detailed lines can be seen in my hugebook, now
almost 20 million positions, available for registered
users; results of coming testgames, mainly on
playchess.com will be included in coming months;
lets see if the Najdorf can still hold against the
English attack (with 6.Be3) ; and as 1.d4 is scoring
quite well i probably also will do some research
into the 'best' (more advanced) defence against 1.d4.

until later
jef