BoD and Bob are teachings of the Church. Once the Feeneyites accept those teachings there will not be any problem. The Church cannot have two contradictory teachings.
BoD and BoB are propositions of speculative theology that have been allowed by the Church.
BoD was rejected by the vast majority of Church Fathers, and the Fathers who believed in BoB felt that it was actually the Sacrament taking place, and not a substitute or an exception.