I try not to trust a line that myself or team didn't run, i think it could just lead to trouble. I'm not sure about leaving "permanent" lines in a wreck, for caves I can see but I'm not sure that applies well to wrecks. Most of the easily accessible wrecks on the west coast are artificial which means a "wide demographic" of divers on them, which I think having any line permanent is a bad idea. Even when my team is penetrating I worry about those "curious" divers following the neat looking line.