More Russian Illusions Than I

Colin Phillips gave a nice plenary talk at the LSA this afternoon on the role grammatical illusions can play in studying the online processing of sentences (was it just me, or did his English accent seem more pronounced than usual? Was this a social register effect or am I off my rocker?).  He drew a really nice parallel with optical illusions and the value they have added to the study of vision.  The point is that there are some sentences that seem perfectly grammatical at first, but upon reflection, are completely incoherent. For example:

• More people have been to Russia than I have.

Most native speakers of English will read this sentence and be perfectly happy, but re-read it a few times. Do you see the incoherence? It's incoherent because ...