when sam harris (e.g. see the google talk uses examples of religious groups
making immoral decisions, I think he is making a category error of the same kind that Nick Kent does when write about rock music (e.g. see this review of his apathy)
it isn't religion - its something anthropologists could easily describe and is a behavioural pattern.
it isn't rock music - its a lifestyle thing - basically NME in 1972-1977 was a lifestyle magazine - those of us who liked music (often the same bands, e.g. CAN, Zep, Pistols, etc) had criteria that we shared - critics like Kent were bewitched by personalities - sometimes, the personality was necessary for the individual to make that kind of music - often not - like the myth of van gogh's madness (in his letters to his brother he frequently described how it GOT IN THE WAY of his art), the destructive behaviour of the various megastars and burnouts he described is interesting, but not because it led to the music or the music was about it.
just so, the behaviour of cultures or social groups (e.g. to oppress women or to encourage suicide bombers) is not a feature of the religion - the religion is window dressing, life style etc - the decisions are made for social reasons
as a scientist, it behoves sam harris to do better - telling people that rational objective thought might lead to better moral decisions doesn't really help - it is like telling keith richard that giving up smack might make his playing in the stones more reliable. it is completely and utterly irrelevant.
it is beside the point.
it is a blues in Eb minor with lyrics from the koran and an album cover with photos from prophets in hell
it is bankers telling the government that increasing tax or NI is a bad idea.
it is beyond the pale, round the bend, up the wall, and thoroughly so.