He could ask the master how is the nature so perfect.
Or could conclude by himself that powders are not single crystals, so that symmetry may lead to systematic overlap and irrecoverable loss of information.
Yes, anisotropic line broadening is rarely observed with cubic compounds unless in very special cases of faulting.
Yes most crystals, when seen through the powder diffraction method, seem to grow along symmetry axis, due to that averaging produced by exact overlapping according to the symmetry.
how then you searched for size anisotropy in CeO2 with ARIT? Or the symmetry restrictions are optional?
Not violating symmetry restrictions you may either have the sphere with the terms 11=22=33 and 12=13=23=0 or something else allowing the 12=13=23 terms to be equal but different from 0. These two possibilities are all you can do in cubic symmetry with h,k,l permutable. If I am not wrong.
Armel
