Arguably the dependence of bending moment on shape is intuitive, but the geometry of developable surfaces is not. Just like in Maxwell's theory of hills and da

Arguably the dependence of bending moment on shape is intuitive, but the geometry of developable surfaces is not. Just like in Maxwell's theory of hills and dales: the location of topographic peaks, saddles etc. is "obvious" but the constraints on where you get saddles and how many, etc. are not. (http://en.wikipedia.org/wiki/Morse_theory http://en.wikipedia.org/wiki/Morse_theory or http://www.maths.ed.ac.uk/~aar/surgery/hilldale.pdf http://www.maths.ed.ac.uk/~aar/surgery/hilldale.pdf) Or the similar territory of the Euler characteristic. You could know polyhedra very well from a physical, practical point of view and never notice it. (http://en.wikipedia.org/wiki/Euler_characteristic#Polyhedra http://en.wikipedia.org/wiki/Euler_characteristic#Polyhedra) Maybe? Anyway, I am commenting because I'd be interested to hear your reaction to the problem stated here: https://www.youtube.com/watch?v=36gOx3dguWs#t=17m35s https://www.youtube.com/watch?v=36gOx3dguWs#t=17m35s