I had similar issues recently:
http://www.grandprixforums.net/f18/i...s-w-32045.html
So far the wires seemed to be the problem. I found a hole in the #4 wire. Exactly like you I would get skips and misses under load. Since I replaced the wires on Saturday, the problem has not returned. I'm running the exact same plugs as you and have been for about two years.
I will continue to monitor and see if the problem stays gone.
I've heard this as well but so far no one has been able to tell me why. I don't mean to jack the thread but I'm curious to know if anyone has any insight...