Mistwell
Crusty Old Meatwad
werk said:See: Blanket Analogy, above.
I already responded that I think it's one of two competing and compelling analogies. Just because someone can come up with an analogy that is counter to this doesn't mean the question is answered. It just means we have two competing and compelling analogies, and hence a tie. And I break ties using the official FAQ from the publisher of the rules.
Blur, as an effect, makes the PC, and hence their image, jump and move about on the edges. People keep talking about how it's just "blurry" because that is the title of the spell. But that isn't the described effect. The described effect is movement-oriented. And movement-oriented effects other than this one all effect the image. If I have a higher dex, even if it is from a spell, the image gets a better AC and therefore attacks have a greater miss chance against it. I really think that is the more compelling analogy than anlogies that depend on a fixed object blocking sight. This isn't the case of a fixed object. It's an effect that makes the image move (or appear to move).