Rayon thread FAIL

Some people love Rayon thread for embroidery. It can be a little glossier than polyester thread, but I can hardly tell the difference. It also definitely has an issue with aging, and people frequently recommend to test it by giving it a quick tug. "Fresh" rayon thread is supposed to have the tensile strength of polyester, older will break fast.
Recently I bought some rayon because that was the only type available at the store in the size and color I wanted.
When I started actually sewing, it was on a free-standing lace design. I sewed it on water-soluble stabilizer, and it looked pretty good, except during the sewing I kept getting thread warnings. It was a mess, and did not stitch out properly.
After I gave up, I checked the thread. It snapped like overcooked spaghetti.
Here are the pictures of the lace as it started soaking, and my little pile of wasted useless thread after I soaked the stabilizer out of it. Click on the pictures to see a closeup.
I'm going to polyester thread exclusively. Not worth my time and trouble to continue with the rayon. At least the store was very nice about taking it back.