  Several papers have been published recently, particularly in the field of
topological insulators, that use a Fourier-transform technique in a way that
can be misleading or otherwise inaccurate, and the processing is not always
described in the Methods or Supplementary sections. This manuscript describes
subtle issues with the technique that have been overlooked in several
high-visibility papers. For instance, many authors make strong arguments
regarding the importance of symmetries and asymmetries in their data, then
enhance the symmetry in their data without accounting for their data processing
steps. A brief analysis of the validity of FT-STM data symmetrization is
provided, alternative analysis techniques are described, and some often
overlooked concerns related to the scattering centers are described.
