An even harder performance test is represented by the larger gramicidin system with explicit side chain optimization. As reported in Figure using the AMOEBA surrogate PES the energy progression is clearly hampered or stagnates after few tens of iterations in the absence of elitism. On the other hand, a (too) high fraction of elitism of 20% increases the variance and does not reach the lowest energies, whereas the putative GM is finally found in 3 over 10 GA runs using a medium 10% rate of elites. Astonishingly, the surrogate GM is also the closest geometry to the DFT-resolved structure that are both reproduced in Figure . The agreement between the AMOEBA and the B3LYP geometries is remarkable with a backbone(heavy-atom) RMSD of only 0.2(0.4) Å.