  The longstanding notion of stripe incommensurability being proportional to
doping, \delta(x) ~ x, in lanthanum transition-metal oxides, La_{2-x}Sr_xTmO_4
(Tm = Cu, Ni, Co), is partly borne out by experiment but also plagued with
exceptions. Future neutron-scattering experiments on cobaltates could provide a
clear distinction whether a linear or square-root dependence, \delta(x) ~
sqrt(x - x_0), is valid.
