I usually travel pretty heavy to ensure I have enough food and warm dry clothes. After this ride and my 600K's I always think I was stupid to bring that much stuff that I never used. That was just extra pounds to lug up the endless hills and through the peanut-butter mud. At least for the 600K brevets you know where your next meal will come from. There are somethings I always have like extra socks if rain is forecasted. Short finger gloves with windproof gloves to go over them plus another thin pair for overnight. For food it is always nice to have a Salted Nut Roll and some Fig Newtons stashed for those stops in the middle of nowhere. I will be packing lots of salt tablets, Aleeve and Chamois butter plus a few gels including one with caffeine for that late night jolt. Speaking of Jolt I also carry some caffeinated gum. Jolt was the first brand I found that made the gum but now you can get several brands. Last year I gave some away in the middle of the night to keep fellow riders awake.
Sunday morning/afternoon as I am finishing up I will again have a list of items that I carried for 330 miles that I never used. Just having them packed and ready to go hopefully will make me sleep better.