I very much agree - everyone needs to confirm everything through personal study and prayer. Some random guy in the cafeteria, vs. disagreeing with the prophet and apostles though - have you ever been daring enough to disagree with the prophet and apostles?
Privately and upon policies, yes. I haven't done so in regard to basic doctrine however.
Talking with my stake president - he shared that he served a mission during the priesthood ban on the blacks, that it broke his heart. I asked "so what did you do? when you disagreed with the policy"? He did not do anything - he just stayed silent, and was happy when the ban was lifted. I told him I did not think "silence" was the correct response to that - I believe it is perfectly fine to disagree with, and communicate concerns about, policies that are harmful and destructive.
I prayed hard, and a lot; I served my mission during those years, too, and the wonderful man I married could have checked off the 'African American' box. So can my kids. He (my husband) was about half native American (we just found that out through DNA from my daughter) and his mother was hispanic with about a quarter black heritage. Now me, I'm just about as 'pure' a Celt as an American can pull off, but my kids have everything in 'em but Asian. They are gorgeous, my kids (yes, I AM biased. Sue me). So the ban on blacks was rather personal for us.
However, we decided that we would pray for this every time, and we did. And that announcement on a sunny June morning was so welcome, and we were so full of joy, that I couldn't contain it in the house. I had to go outside and shout for it.
Because yes, while on my mission I had to try to explain it to someone, and I just said....I don't know, but I have faith that it will all turn out well.
It did, and within four years of my marriage.
Works for me. What that tells me is that if we hold to what we truly believe to be true, and have faith that God will straighten things out if we are faithful, then...He will straighten things out. So far that seems to be working.