Those who want to turn gospel teaching into academic style teaching where quotations are the measure of truth instead of the Holy Ghost are in an interesting conundrum. They believe that by insisting on that they are offering safety. Interestingly, every one of the major Christian religions backs its doctrine with extensive quotations from such figures as Christ himself and the original twelve.
Without the Holy Ghost being the key to both learning and teaching, there is no safety in quotations no matter the source.
Any doctrine that casts out the Holy Ghost as the means by which we learn and by which we teach casts out the lifeblood of truth.
After all, can we gain a testimony except by revelation through the Holy Ghost? If beginning of the path is marked out by revelation, in the form of gaining a testimony, do we really believe that the path itself is to be traveled by some other means.
In D&C 50 we learn that gospel teaching is teaching by the Holy Ghost, where the learner is learning by the Holy Ghost. Interestingly, no mention of authoritative quotations is made.
If God's description of how his gospel is to be taught in the last days requires the Holy Ghost but makes no mention of authoritative quotations, isn't that enough of an authoritative quotation for us to throw out the requirement of authoritative quotations and replace with God's own required method: that it be taught and received by the Holy Ghost.