I was there too for the testing of the 9 Leonardo guitars and I agree that the guitar-maker and the player make all the difference, it is not the wood or lack thereof. The paper guitar really responded well, just as Walter's guitars generally do.
I enjoyed Gerhard's lecture on Hauser which filled in some gaps in my knowledge about guitars and makers. It was also a pleasure to meet James in person and appreciate the wonderful work he does both on his guitars and with his students. The festival was great!