I think this begs the question, "how much additional weight is really significant." My guess is that 68% of backpackers (all ages and conditioning) carry a base weight of between 19.5 and 47.5 pounds. At 16 pounds you are still probably in the 1 or 2% of the lightest. On week summer trips I share a 2 pound tarp-tent (Squall)with a friend. I have a 800 gram (Lafuma) sleeping bag and sleep on a 14 ounce ridge-rest mat. Colin Fletcher says pare the weight down unmercifully, but if you need it, take it. I currently have my base weight down to 13 pounds. (age 71, 179lbs 5-9)
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Jim M