As if I have any idea what I'm doing. I did a little googling last night and found unanimous opinion that this didn't work on Sempervivums, but was useful on Echeverias and various other succulents. Seems to me if it did work it would be in practice and it would be known by now. But that's not always the case. Sometimes it takes a clueless ignoramus to try something that goes against conventional wisdom to discover something unconventional. What have I got to lose.
OK, I left those semp pieces out in the open air for 48 hours, in a bright but shaded outdoor area. Hopefully to dry up the wounds in the stem. I then selected a modestly sunny area and laid the pieces out on the soil. I made little slopes in the soil so that the semp leaves could stay upright and the stem portion would contact the soil instead of being lifted in the air.
Last night I watered the area moderately. This soil is sandy, drains fine, and remains moist but not sticky in any way. I will keep it lightly moist.
Last night at "planting" time the pieces were moderately limp and feeling pretty anemic. This morning they are much firmer and feel alive. Maybe they took in some water through their leaves overnight or maybe it's just the coolness of the nighttime air... I couldn't say. But it does suggest that they are at least alive and that's all I'm asking for at this point.