Have you been on a load-pro training course or something?
You have always had to load a circuit to volt drop it, its nothing new. You just turn on the circuit or load it with a halogen bulb or use your $100 test leads

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Its not rocket science
In fact what they have taught you is factually incorrect, If you have an open wire/fuse you dont have to load it and volt dropping will still find it
No, I don't even have a set of them. They just seem to be the easiest and cleanest way to do it, if you're going to use a DVOM. I'd rather use a test light. And FWIW, they're only about half that cost on Amazon.
I don't know who you think 'they' are, but 'they' haven't taught me anything. We're not talking about opens, we're talking about poor connections that don't allow for any decent amount of current flow.
That's exactly it, you have to load the circuit; you were talking as if you could somehow do a voltage drop test on an unloaded circuit. I'm simply saying that the test light is the quicker and easier of the two, if you're trying to voltage drop a circuit. No trying to energize whatever component is on the circuit, or rigging up another load like a bulb (if you're going to do that much, then why not just use a test light? Unless for some reason you're interested in exactly what the available voltage is).
No, it doesn't show you what voltage there is, but almost every corrosion or poor contact issue I've had that's been found through voltage drop testing, it's quite a noticeable difference in light output between good and bad.
Regardless, to each their own. My methods have always worked fine for me, and apparently yours for you.