John---you and Doug are going to get along great
I have a full Topps set run and they are all in sheets in binders, and any that were graded when I got them have long since been freed to their natural state. I can not say for certain I do not have altered or trimmed cards or resealed packs in my collection, but neither in my view can the graded guys. What I do know is that I will be the judge what cards go in my collection without the aid of a minion at a grading company who knows less about post war cards than I do.
But, I will admit I am just in this as a hobby. If you are an investor, or a hobbyist/investor, grading is a fact of life