I too used to give PT's and other talks based entirely on what I could clearly see the bible really said, and not containing anything extra i.e WT contaminated.
Nobody dared to contradict what I said, they knew I would simply flop open my Bible and say, "what does that mean then ?"
The closest I ever had to a challenge, was when I gave an "Away" talk, and an Elder from the Hall I was visiting said to me afterward that he had given that same talk some time before , and he didn't recognise it when I gave it ! What a compliment !
I explained to him my method, which I probably should not have done in hindsight, but nothing came of it, in fact that Congo. requested that I visit and speak again, even though they knew I had ceased speaking in my own Congregation.
My method was to analyse what the cited scriptures really said, to strip out all dross from the outline, to shufffle the sub-sections around in to a logical order
(the outlines were dire, dry and put together by a disinterested bethel Boy) to concentrate on what we could actually do as Christians, and to finish on a motivating "high".
I doubt that Elder knew what I was talking about, but it shut him up, because I was sincere, I really, then, wanted to help my "brothers and sisters" find a way of living their faith that worked.
What this rather long post is leading up to is, if the guy who you heard was genuine, he may well soon be fully awake, and joining us here.