As a Christian, I don't have any objection to The Rule.
As an American who believes in the separation of church and state, I definitely understand and sympathize with the instinct that, although religious laws often provide good moral guidance for secular codes of conduct, the two serve distinct purposes. You don't have to reject the ten commandments to recognize why we need more graularity and detail in actual laws regarding murder.
As a developer, I recognize that there are concrete and specific ways in which documents like The Rule fail to meet the pragmatic needs of a code of conduct, including:
1. clearly delineating acceptable from unacceptable behavior
2. establishing a reporting mechanism
3. codifying specific consequences for doing things that were clearly delineated as unacceptable.
A perhaps important thing to realize about monkish orders is that they were intrinsically self-selecting; you didn't need to worry about the "spirit" vs. the "letter" of the law. Monks did not need to worry about people misunderstanding ambiguously stated laws (e.g. "love thy neighbor"). The process of joining a monk-hood or a a religion includes an indoctrination/inculcation/instruction into the "spirit" of the law. Sending a pull or posting on a message list is not even remotely similar.
I.e., if you want to extend the development community beyond a small a close-knit group who understands each other, then you need something closer to laws than to religious commandments.