Even for gentle refinement, the changes to the reference weights can be noticeable. For θ = 10, we found the top 50% of the conformations to carry ∼80% of the weight in our three examples, consistent with the Gaussian approximation (Figure ). Despite the small entropy values of S KL ≈ 0.2 to 0.4, these changes to the weights are sufficient to substantially reduce the deviations from experiment (see L-curves in Figure ).