Variation in best-fit Kroupa (left) and Chabrier (right) mass functions as open cluster stellar populations are dynamically depleted according to the H. J. G. L. M. Lamers et al. (2013) prescription, for both a Kroupa (top) and Chabrier (bottom) IMF. Depletion prior to mass segregation (yellow) primarily alters the normalization. After mass segregation, further depletion increases the characteristic mass for the best-fit Chabrier mass function, but the break mass for a Kroupa mass function is nearly invariant. This occurs regardless of whether the true underlying IMF is Kroupa-like or Chabrier-like. Thus, the choice of a Kroupa mass function breaks the degeneracy between dynamical evolution and IMF variation that exists for a Chabrier fit.