I can't imagine what keeps him bouncing back and forth like this. Perhaps it's just a spiritual instability. Maybe he's simply unable to make a decision and stick with it.
Or, perhaps he never really left the Episcopal Church.
It was a strange experience when he visited our parish, after he had become a Catholic. He arrived in clerical dress, wearing his pectoral cross and his episcopal ring. I remember thinking, "How odd." Now I'm thinking that perhaps he really doesn't see any difference between being an Episcopalian and being a Catholic. Apparently he's been receiving Holy Communion in both places concurrently for some time. Either he's completely confused, or he's completely indifferent.
One thing's for sure. He's a better Episcopalian than he is a Catholic. Not that it counts for much.