The statement "better to have one healthy baby than two disabled ones" sounds fine, in theory - but this is not theory, this is the lives of two children, as well as their parents, and the doctor(s) who must make the agonising decision. Some conjoined twins have grown to adulthood, and would be aghast at the notion of on perishing to 'save' the other. Conjoined twins know no other existence, problems we would imagine to be insurmountable are normality to them - who makes the decision about who lives, or dies? One healthy baby from two disabled? This is children's lives, not an Airfix kit. Think about it, how would you feel if it were your twins ... or you?