Make naming of energies follow convention.
Don't actually need to make separate variables. They're cleared and calculated each time-step, and no further operation is done after this method, just printing and global operations like this.
evidently, since _Wext is a cumulative variable (is not calc'ed from scratch every time-step), you can't just add up the local ones each time step. Introduced _WextT to act sum of local _Wext's and calculated each time-step.
make it so that _numFrag and _DSum are reported correctly in output, and fix some tabbing.