4. Do seers/prophets know what is correct and what is incorrect?Only as it relates to what the Lord is telling them. Otherwise, they are entitle to their opinion.The problem is that LDS Prophets also have a fundamentally difficult time distinguishing between their own opinion and what the Lord is telling them.
If they can't distinguish between the two, how can others?
Are LDS Prophets also entitled to their opinion as to whether they are getting revelation from God?
Also, bc space, I'm wondering, what's the decision rule for determining whether a prophet is speaking his opinion or relating what the Lord is telling him?
The way to know has been around from nearly the beginning. The first principle is D&C 107 in which we see that the FP and Qo12 have equal authority. The implication is that both bodies must agree on doctrine.
LDS doctrine and policy on this matter has been around since I've been cognizant of the matter (30+ years) and has recently been reiterated by the Church.....
Not every statement made by a Church leader, past or present, necessarily constitutes doctrine. A single statement made by a single leader on a single occasion often represents a personal, though well-considered, opinion, but is not meant to be officially binding for the whole Church. With divine inspiration, the First Presidency (the prophet and his two counselors) and the Quorum of the Twelve Apostles (the second-highest governing body of the Church) counsel together to establish doctrine that is consistently proclaimed in official Church publications. This doctrine resides in the four “standard works” of scripture (the Holy Bible, the Book of Mormon, the Doctrine and Covenants and the Pearl of Great Price), official declarations and proclamations, and the Articles of Faith. Isolated statements are often taken out of context, leaving their original meaning distorted.
Approaching Mormon Doctrine 4 May 2007
In other words, you know for sure if what a prophet or apostle speaks is doctrine when it is found published in an official work of the Church. Minor caveats would be "of latest date" and "presentation". For example, the LDS Edition Bible Dictionary, even though published by the Church, is not doctrinal beause it says so itself in it's own introduction.
This has always been the teaching for as long as I can remember stemming out of the CHI book 2, missionary directives, teacher preparation classes etc. And then there is that pesky (for exmo theories on doctrine) D&C 107......