Principles
Four principles govern the practice. Each is a test that can be failed.
Provable
If something is claimed, there must be evidence to prove it.
Derived
If something can be determined from the record, it must not be decided.
Traceable
If something is claimed, decided or moved, there must be a path to what produced it.
Invariant
Whatever the size of the work, or the kind of actor, the same process applies.
Using them
They are used twice. When defining the practice: does this decision serve a principle? And when applying it: which principle is this choice targeting? A practice whose principles are only read at the start is a practice with four decorative sentences at the front.
Anything that traces to none of the four does not belong. That is the disposal rule, and it applies to mechanisms already in the practice as readily as to proposed ones.
Each of the four states something that could be otherwise, and each can be checked against a specific decision. A practice whose principles cannot be failed has four sentences that approve of everything — including the next mechanism nobody should have built.