The probe theory was Duncan Lunan's.
I read about it in college. There's a Wikipedia article about Lunan here.
When I was even younger, I read a cool book called Strangely Enough by C. B. Colby, which had enough bizarre mysteries in it to keep this particular board going for years. Some of them kept me awake at night. I still have an old hardcover copy.
One of these mysteries was the famous "KLEE call sign" mystery, which seemed to be a very strange LDE. Unfortunately, the real story is more mundane.
More on LDEs here.