Well, seems to me you'd just sheet in, turn the wheel all the way upwind, and see what happens.
If the boat tacks, it ain't working. If the boat fore-reaches at 1 knot with the helm lashed, riding like a cork, it is.
Success might depend on how many reefs, your specific keel, and the sea state.
I've heard of the main-only heave to but never tried it. Not immediately aware of the benefit of not using a backed jib along with the main.
That usually works for me, although I haven't tried it in heavy air and breaking seas.