"What about Narrowing social gaps", the readers keep saying. Indeed, isn't it easy, waiving slogans left and right? The truth of the matter is that there is nothing between a private/elitist system and social gaps. Social gaps are about attainment - the more education the individual attains, the greater her life chances are (chances of possessing social goods - power, prestige, money). Look at the American statistics for private vs. public schools; dropout rates are about the same. The variation in higher education attainment is not a product of elementary and secondary schooling as it is the product of home culture that affects aspirations and motivation.
Private schools look bad, and it IS very easy to attack the writer of this article. A differentiating system? Not in our school! We are a socialist society, we care about equity... Well, evidently, social gaps will probably not widen due to private schools, just like they will not narrow in an all-public system. Today, when all Israeli kids attend public schools, the rich are able to maintain their advantageous status and transmit it to their kids, regardless of the nature of their schooling. Private schools will not contribute much here, but maybe only - as have been commented before - make an existing situation more visible.