  We present a novel, self-consistent and robust theoretical model to
investigate elastic interactions between topological defects in liquid crystal
shells. Accounting for the non-concentric nature of the shell in a simple
manner, we are able to successfully and accurately explain and predict the
positions of the defects, most relevant in the context of colloidal
self-assembly. We calibrate and test our model on existing experimental data,
and extend it to all newly observed defects configurations in chiral nematic
shells. We perform new experiments to check further and confirm the validity of
the present model. Moreover, we are able to obtain quantitative estimates of
the energies of $+1$ or $+3/2$ disclination lines in cholesterics, whose
intricate nature was only reported recently.
