Attempts to identify monomers involved in a defect can use simple structural and energetic parameters (or fingerprints), such as, for example, the solvent accessible surface area (SASA), the interaction energies (∆E) of the individual monomers in the assembly or the coordination between the cores in the stacking (assessing somehow the stacking order). Such analyses allow to single out monomers that are more exposed to the solvent than the average (SASA>avg, Figure ), and that also belong to domains of the fiber where the assembly is less stable than the average (∆E <avg, Figure ). However, this approach has at least two crucial weaknesses. First, it is based on heuristic descriptors, that rely on prior chemical intuition, making the analysis somewhat circular: