I Just spoke to Wendell Diller at Magnepan and reducing the speaker cables has zero affect unless your running 15-20ft of cable. I don't know why we get all this misinformation on Maggies.We've built short speaker cables for a number of our customers who are really happy with the results. I would not want to cut an $8000 cable either!
But the difference was not trivial- shorter cables really help if you are running tube amps.