Excellent points. From a theological viewpoint, all relics, genuine or spurious, are useful so long as our faith brings us to God.
My only point was that, given the antiquity and contemporary nature of the tradition, dismissal of the story of the discovery of the True Cross as a mere "legend" seems a little harsh.
Is my faith dependent on those relics--or any relics--being genuine? No, of course not. But I am interested in the truth.
I would agree if it was the only thing I said.