The technique described in the original question was borrowed from my novel The Weird of Hali: Innsmouth, in which one character teaches it to another to deal with hostile magic. Yes, it's meant to be used for negative experiences; yes, you're in the habit of doing things the other way around, and breaking that habit would be useful; yes, this is what detachment is about. As for the traditions that focus on the full in-the-moment awareness, keep in mind that spiritual traditions vary not only in their methods but in their goals; that's one goal, detachment is another, and there are others still.