just fyi, my y-a-w-n was a short version of my thoughts.
the longer version is here's yet another thread with circles of: you are crazy to only carry 4 pounds, you'll die/you'll thrive/you'll challenge yourself, 5.5 lbs isn't XUL it's SUL/simply UL/hyper-light/supera-hyper-light, i could do it lighter/better/faster/smarter, cuben is too light/expensive/fragile/robust, i do/don't learn from XUL.
here are my thoughts. alan's list seems fine (though probably uncomfortable at night and/or in colder rain) for a few day trip in relatively mild weather. he's got shelter, rain gear, sleeping "bag"/insulating garment, stove, etc. 75 miles in three days isn't a death march by any stretch, at least for lots of people - it's 8-9 hours of hiking (on reasonable trail). there's lots of interesting and insightful cross-pollination between the fantatic fringe and the rest of us, regardless of what XUL/SUL/hyperlight/UL means to you. the fanatic fringe is definitely as exercise in diminishing returns from a practical standpoint - i definitely notice a difference between 8 pounds and 15 pounds in a 30+ mile day, but i doubt i'd care much between 4 and 5.