John, as a user of both old and new lenses, I do have my preference with respect to focus throw, but in at least one particular case, the Noctilux, you need the long throw to focus accurately at very wide apertures. So I don't think their reasoning was that a shorter throw improves accuracy. Its possible that improved mechanics made shorter throws possible - certainly the trend over recent years has been for the throw to become shorter.
I don't know what Leica's rationale was, but from a usability perspective I do prefer the short(ish) throw of the modern lenses. I am lucky enough to have 20/20 vision in my VF eye so a short throw really suits me and what I shoot. I have a modern Leica 24/2.8 and a 1960's CZJ 25/4 and the difference in usability is unbelievable. It makes you really respect people like Josef Koudelka who shot so many incredible pictures with the very same CZJ lens under the most difficult circumstances imaginable.
