To BOders, the councils teach in parables so only theologians understand what is being taught - except when it comes to a few certain things - -like "the desire thereof" means BOD has been defined.
Then you have Ambrose saying "When a doctrine is taught in an ecuмenical council, it is de fide." Yet he rejects de fide teachings from ecuмenical councils as though rejecting them were the rule of faith taught in ecuмenical councils.