What you mean is that there is a psychological mechanism—a consequence in your “thought experiment” of the monastic practice—that internalizes an “identification” between two members of the same group. What I don’t see is a sharp distinction between “identification” between members of the same group and “loyalty” within the group.
This phenomenon of “identification,” when differentiated from “affect,” requires a peculiar psychological construct. It occurs to me that it could be an abstraction of affection, which doesn’t require personal proximity between those who share an ideology of affection, if such an ideology could exist. I find it difficult to believe that an “identification” not equivalent to “loyalty” can occur without an affective element (one can be loyal to communism or to Christianity, but I cannot identify with Jesus, whom I love, in the same way as with the historical figure of Lenin).
We can love all our fellow human beings within an affective ideology (our faith is limited to believing in a life governed by patterns of affective and caring behavior), but at the same time, we only personally identify with those who share this belief in universal love.
Is it possible to construct such an ideology? It has never been done, but some Christians have claimed that “God is Love”… which some might interpret as meaning that God does not exist, but that Love does exist as an affective abstraction, which can be symbolized and therefore also psychologically internalized within a context of shared belief (ideology).
So far, no one has undertaken such an experiment. Believing in “Love” (or its equivalent behavioral pattern of benevolence) would imply believing in a personal learning process to achieve a model of behavior at all levels (at the economic level, this would involve altruistic behavior).
The point at which “effective altruism” transcends the triviality of choosing “more over less” is precisely when principles depend on behavior. A “behavioral ideology” is something that has not yet come into being.
However, it becomes even more trivial when the principles of human behavior are detached from the idea of virtue or lifestyle.
It’s trivial to worry about how to spend resources on certain charities when one doesn’t have them.
The non-trivial consequence of an ideology centered on prosocial behavior patterns (financial charity, but not only) is the belief that the primary effort of such a movement should be to increase the number of people practicing charity. This requires effective psychological strategies that make a lifestyle based on cultivating benevolence (of which charity is a necessary consequence) appealing. For example, one hundred years ago, the founders of “Alcoholics Anonymous” had a very good idea.