I think you are on the right track....but....

In order to achieve your goal, you can't limit this to backpacking. You have to do it every day. The only way for you to be comfortable sleeping on the hard ground while backpacking is to do it at home all the time. The only way to be comfortable walking barefoot is to walk barefoot all the time. If you only do it a couple times a year, then it won't take too many times before you are back to your "old" ways.
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