^Read my post a couple above my last and you will get your answer to what I have learned from ketamine. It has taught me that my memories are precious and that I should try to learn from them and seek the beauty in them rather than try to hide from them. I had a horrible heart break (a girl whom I loved deeply did me over right well after years of love, turned out to be somebody she wasn't, and it was hard on me)... all my memories with her I wanted erased because it brought so much pain thinking about it. I took ketamine one night and was reliving some of our most beautiful times together and I realized that I still had a good time with her and that the girl I loved was in my head, but the memories were real, and that I should look back on them as good times rather than try to forget a part of my past, and thusly, a part of myself.
I will give you that acid probably has a far greater frequency for causing change, but you cannot simply make a blanket, every-case statement from it. As I said, the psych of those going through the experience will have a lot to do with how the substance effects them both in the present and the future.
*Note: After reading your statement again, it could be taken as not an every-case statement but just in general, so I apologize.