The theory that describes the arising twist-bend periodic walls at the neig
hborhoods of the Freedericksz critical point affirms that the mode with the
fastest initial grown will fix the observed properties of these patterns.
From this principle it follows that just above the Freedericksz threshold t
here is a region where this leading mode becomes null and, therefore, a hom
ogeneous bending of the director would be detected. This prediction was not
confirmed by the experiment and walls with very well defined wavelength we
re found. We will shown here that around the Freedericksz threshold the fas
test growing mode can not be defined and a new way to compute the observed
structures will be proposed.