I almost always experience some sort of plurality as you put it. My body being multiplied and copied over and over, looking at copies of copies of myself, that sort of thing.
As to what it means, that's the real difficult part, isn't it?
Salvia is definitely a teacher, giving us lessons to decipher, but those lessons are often obscure and bizarre, metaphorical, or may even seem completely devoid of any meaning at all. I like the mystery and "magic" as I put it, it keeps me coming back. I want to understand things, and I think Salvia is something that will take a very long time to fully understand, if ever.