"techniques average over an ensemble of many molecules... These averages are blurred by the structural differences from molecule to molecule, requiring models that incorporate structural heterogeneity to explain the data" A big hurtle is just amount of data needed / how to show heterogeneity

When structural papers show heterogeneity, it is often expressed as "error" and not error in the measurement but error in the locality. Its a precision problem not an accuracy problem and communicating that or even drawing specific conclusions can be difficult / misinterpreted.