Regina, Saskatchewan; Canada
My only caveat is that religious doctrines are, by definition, unstable as they have no real reference point. How do you convince someone of the rightness of a "good" interpretation?
I won't try to speak for other systems. I have learned a lot about Islam in the past few years and now have a lot more faith in it than other systems. One of the reasons is that I find it does have very strong and stationary "reference points" and doesn't let itself become assimilated into self-centered secular liberalism and the moral free for all that has come upon much of the world today. It is markedly more strict and self-preserving than other religions and systems; it needs to be if it is going to continue to be itself as a comprhensive way of life, but one that takes part in all spheres of humanity instead of being forced into the closet. Different opinions can be shared by Muslims about aspects of their religion, but opinions need to be strongly supported by the sources and the community in general in order achieve any level of respect or authority. The moral and legal commitments are set out by the three main sources: The Qur'an, The Hadith, and the Shari'ah. If something isn't unambigously supported by these sources, then it will not be supported by the community in general, and if something is not supported by the sources and the community in general, then it has no legitimate standing in Islam at all. This prevents Islam from being something subjective that people can make whatever they wish of or moral free for all in the name and belief of God, because it is so thoroughly source-and-community based.
That is how Islam has very strong and steadfast "reference points" for determing good practices.
But a similar principle is used in other practices, including non-religious ones. Anyone could come up with his or her own notion or approach for what is "good dentistry", but that doesn't mean we recognize everything as good dentistry and that everything will be given moral or legal permission as being included in dentistry. If you know of a dentist that used a chainsaw and hammers, either doing so against the law, or because his country or community doesn't have morals or laws against it, would that be what you go by, generalize, or think of first when you think of "dentistry"? Or if your country for some reason lacked much dentistry but you could still read widely about it and learn about dentistry in the world, instead of going by how dentistry is practiced in most places, or in the most advanced places, by most dentists, will you still go by tjat worst-case scenaria of someone using a chainsaw and hammers, instead of the most common-case or far better-case scenarios of dentistry praticed with far less dangerous tools? Surely not.
Usually it doesn't take much to know a horrible example is a horrible example of something, whether you are looking at a religious practice or medical practice and that it shouldn't be used as an example to generalize it by. But bias and media can exploit a bad example so excessively that it soon becomes a blindfold to the immensely larger truth.