Oddrock, I won't be debating any who, hows or whys on this particular string because you requested that we not and that you were just interested in markers and signs.
I will say that I agree with a lot of your last post. There were other people here, long before Columbus, and some of those people were looking for things of value. It's only human nature that other "groups" that came along might try to find what anyone before them had found or hid.
I also agree with following trails. I work a trail as a specific type, outlaw, Spanish, (even KGC Hoss), until I find something that says otherwise. To me, it's all about interpreting the clues and getting to the end.