Much of the debate between Cornish linguists centers on prosody (i.e. those features of pronunciation which are normally not explicitly noted in writing, like stress, intonation, length, breaks and so on – one could sum it up as the rhythm and melody of a language). A central concept in this respect is the so-called Prosodic Shift which Nicholas Williams postulated for early Middle Cornish: he claims that before the earliest Middle Cornish texts were written, Cornish exchanged its inherited Celtic rhythm for an English one. Ken George disputes this; in his earlier works he claimed that this change did take place, but not before ca. 1600. He has recently adapted his theory and now claims that it did not happen at all, and that the rhythm and melody heard in traditional Cornish English pronunciation of Cornish place-name does not represent how Late Cornish sounded. What this new twist to his theory does not explain well is why, from 1600 on, so many vowels which had been (half-)long originally are marked as short in the texts. Such massive change in spelling at least raises the suspicion that the original rhythm of the language did in fact change.