Views are an imperfect abstraction (as usually implemented). Plus, pre-many-to-many-ing all relationships will make for a notably slower system even if views hi

Views are an imperfect abstraction (as usually implemented). Plus, pre-many-to-many-ing all relationships will make for a notably slower system even if views hide many-to-many-ness. (As I mentioned elsewhere, one often can't know which relationships will grow to many-to-many over time.)