Definitely agree with Woodspirit here. The knife comment does seem to be creating a mist of rage that is obscuring the real intention of the post which was 'how far can I go with regards to shedding unnecesary kit but still spend the whole night outdoors?'
Boatman - my childhood was filled with similar pre-war tales courtesy of my Nan. Very long, care free walks and cycle rides through several counties to visit friends and relations that most people would refer to as an endurance race nowadays. Camping trips with gear that should've been in a museum... Most definitely inspired me to do what I do now and I could sit here now and reel off any number of similar accounts from my own childhood/young adult adventures, attempting to emulate the oldies. However, if I take off the rose tinted specs I remember that the minimalist nights out were often at the height of summer and any that weren't were sleepless, shivering filled episodes. Something to look back on and say 'blimey - I was lucky to get through that in one piece' but not really to be recommended as a general advice to those looking to sleep outdoors with less kit. 'Plan for the worst, hope for the best' will ensure that everyone comes home safely.
Having said that, I remember one long night when myself and a friend set off to walk the twenty or so miles across the South Downs to where we knew a couple of girls we fancied were camping as part of a DoE award scheme. It was getting dark when we set off and it rained cats and dogs all the way there as we trudged through the night. We didn't have a map but we knew roughly where the village was so we skirted the roads and country lanes using the road signs to keep us on track. We also knew the name of the farm where they were staying but even so, couldn't find it when we eventually arrived at the village (I found out after that it was just beyond the village boundary!). Disappointed, we curled up in a bus shelter to try and get some sleep until people started getting up for work (it was already getting light so probably only had an hour of snooze). We were wearing army poncho's but our clothes were pretty damp. I think that without shared bodywarmth we would've got pretty cold. We were also younger and fitter which counts for a hell of a lot when planning these hare-brained schemes. My little boy runs round in a vest all day long without looking the slightest bit cold while I sit there in a great big woolly pully feeling chilly. We're all calorie burning furnaces when we're younger. When your metabolism slows down and calories seem to be being stored 'for a rainy day' rather than furiously keeping the youthful engines chugging away, I think we're less able to cope with such crazy antics so have to plan accordingly.
Anyway, we walked back to the nearest village with a train station and caught the train back home again for a slap up feed. This is the other important consideration...we had somewhere warm to go and get dry...and food to re-fill the energy tanks. The minimalist camper (especially those going further afield) needs to make allowances for several days out of doors. One cold, possibly wet night might be do-able but if your personal situation can't be improved upon before the following night then that's when the human body might've been pushed beyond it's limits and you find yourself in trouble. Just a few key items of kit can ensure this doesn't happen so it's important to know what your absolute bare minimum is, kit-wise to ensure your own safety and comfort.
Anyhoo - off up the woods now!
Joe