One reason for me bringing up this issue was because while I was working on the GTG Naked Warrior progressions, I felt that I still needed to maintain some kind of overall physique, and pushups (often with a heavy backpack) fit the bill quite nicely. So, I'd do sets of one handed pushups at one point in the day according to the book, and then a lengthy string of sets of 10 two handed puhsups at another time of the day. I was lucky enough to find chinup bars aplenty where I was staying, so I also did hefty chinup workouts. The one legged squats were a nice compliment to the extensive walking and hiking I was doing.
If I have one overall reflection on my own (quite unprofessional and hacked) work with the Naked Warrior programme, it's that it does indeed make me super strong and fit BUT in spite of being lucky enough to be able to add in chinups daily, my lower back (as the book says) was not getting strong or every really staying strong. While I was perfectly strong enough in every other way to resume my S&S workout when I got back home after 2 months (because of the Naked Warrior training I had been doing), my lower back was not ready, and I ended up hurting myself a bit in that area.
Anyhow, the point of Naked Warrior is to do the best we can with no equipment whatsoever, and it's sheer brilliance as far as I'm concerned. I never need to feel afraid to leave my ketlebells behind again. I will, however, actively search out something heavy to at least do deadlifts with to maintain my lower back strength somehow or other, next time.