If you go back to the immediate context of Brigham Young stating that his sermons are scripture, you will easily see that this debate is over and dianaiad is correct (in that Brigham Young clearly gave qualifications to which of his sermons can be considered scripture, and certainly did not mean that all of his sermons were scriptural):
Journal of Discourses 13:95
"Well, brethren and sisters, try and be Saints. I will try; I have tried many years to live according to the law which the Lord reveals unto me. I know just as well what to teach this people and just what to say to them and what to do in order to bring them into the celestial kingdom, as I know the road to my office. It is just as plain and easy. The Lord is in our midst. He teaches the people continually. I have never yet preached a sermon and sent it out to the children of men, that they may not call Scripture. Let me have the privilege of correcting a sermon, and it is as good Scripture as they deserve. The people have the oracles of God continually. In the days of Joseph, revelation was given and written, and the people were driven from city to city and place to place, until we were led into these mountains. Let this go to the people with “Thus saith the Lord,” and if they do not obey it, you will see the chastening hand of the Lord upon them. But if they are plead with, and led along like children, we may come to understand the will of the Lord and He may preserve us as we desire."
Journal of Discourses 13:264
"Brother Orson Hyde referred to a few who complained about not getting revelations. I will make a statement here that has been brought against me as a crime, perhaps, or as a fault in my life. Not here, I do not allude to anything of the kind in this place, but in the councils of the nations–that Brigham Young has said ‘when he sends forth his discourses to the world they may call them Scripture.’ I say now, when they are copied and approved by me they are as good Scripture as is couched in this Bible, and if you want to read revelation read the sayings of him who knows the mind of God, without any special command to one man to go here, and to another to go yonder, or to do this or that, or to go and settle here or there. "
It does not matter whether other LDS authorities claimed that one did not need “thus saith the Lord”. We are talking about what Brigham Young meant when he said that “I have never yet preached a sermon and sent it out to the children of men, that they may not call Scripture”. The immediate context of his statement shows that he did not mean that all of his sermons were scriptural, but that he must first correct that sermon, and they must be copied and approved by him. It is therefore dishonest to claim that every sermons preached by Brigham Young is scriptural for LDS, when they don’t meet the requirements set forth by Brigham Young himself about his own sermons.