Yes Julia Child's flushes are without ES they work too, a lot of people do it without ES, but people with calcified stones who are trying to get 24 mm stone throug a 6 mm duct prefer to stick with the ES. Some people do Julia's flush but add the ES at night.
Andreas does not say it hurts the kidneys. But it might be the proces of cleaning that leaves things in the kidneys, that is not what he says, but I assume the first letter writer meant that. Correct me if I am wrong.
One curezone member did research about the ES //www.curezone.org/forums/m.asp?f=565&i=474