I understand that the peak-width of diffraction data increases with increasing amounts of heterogeneous, localized (AKA "micro-") strain. So, if you have a single crystal with atomic impurities in it that each create micro-strain in the lattice, you would expect the amount of peak-broadening to scale with the amount of the impurity—Right? But, if there is enough impurity in the crystal, eventually the impurities would be spaced close enough together that it seems the micro-strain fields associated with each impurity would start to "blend" together into something more homogeneous, and then peaks would actually decrease in width (and probably shift)—Right? Am I correct here? While there is plenty in the literature that describes the effect of micro-strain on diffracted peak width, I can't seem to find anything in the literature that describes when inherently heterogeneous micro-strains in a lattice might become closely enough spaced to diffract as a homogenous strain. Basically, I'm looking for journal or textbook references to guide me. Thanks!