While sampling this 2:2 turn in AMBER14SB is sufficiently rare as to dominate the slowest kinetic timescales (and in turn produce a large VAMP-2 score), further analysis suggests that such conformations are unimportant to the overall folding mechanism of chignolin. For one, coarse-graining of the folding dynamics into folded, misfolded and unfolded macrostates (see below) shows that the 2:2 turn conformation fully belongs to the unfolded macrostate, and that macrostate populations are insensitive to presence or absence of dihedral featurizations (Figure ). Moreover, similar dihedral analysis for the other eight force fields shows that many of them also sample the 2:2 turn (Figure ), presumably with enough frequency that it does not dominate the slowest timescales. Simulations performed in the AMBER99 and AMBER99SB force fields do not sample the 2:2 turn at all. For these two force fields, attempts to build MSMs using backbone dihedrals alone-as well as backbone dihedrals combined with inverse distances-failed for models with more than 10 microstates.