With all respect, useful is a term subjective to our own reasoning however.
You could have 5 uses for a hammer, I could have 3 or 207, another person could see no use at all for a hammer.
I'm not saying that "from one's relationship or definition of god, we can gain insight to their relationship or definition of government." (or vice versa)
^^^^ That's not what I am saying.
Can a school determine how a child behaves toward their parents based on a test taken on a teacher-student relationship, no.
I think perhaps you misunderstood or perhaps my vagueness allowed space to infer I