reset_association

# File activerecord/lib/active_record/associations/preloader/through_association.rb, line 70
          def reset_association(owners, association_name)
            should_reset = (through_scope != through_reflection.klass.unscoped) ||
               (reflection.options[:source_type] && through_reflection.collection?)

            # Don't cache the association - we would only be caching a subset
            if should_reset
              owners.each { |owner|
                owner.association(association_name).reset
              }
            end
          end