I was participating in a 33 mile charity ride this weekend and had left the panier packs on. I did remove the non essential stuff (i.e. no rain in forcast so rain gear came out), no spare cloths, and only a little extra food and drink as I was not sure what I'd have available during the ride. This dropped my packs by about 6 Lbs, but I kept the toos, spare tire, and pump. Good thing I did. At the first rest stop there were three people I was able to help adjust their bikes quickly. I had the alan wrenches with me and that is all that was needed. They could have waited for the repair truck to come, but that might have taken a while. I felt nicely vindicated for always carrying extra "stuff" with me. I was glad I did not need the spare tube or pump, but it is nice to know I would have been ready if needed.
Happy riding,
André