  We revisit the case of magneto-rotational evolution of neutron stars (NSs)
with accounting for changes of the angle \chi between spin and magnetic axes.
This element of the evolution of NSs is very important for age estimates and
population modeling, but usually it is neglected. In the framework of two
models of energy losses we demonstrate that unless NSs are born with the
inclination angle \chi_0 very close (within 1 degree) to the position of
maximal losses, pulsars with short initial periods quickly reach regions of
small energy losses (aligned rotators in the case of magneto-dipole losses and
orthogonal rotators -- in the case of current losses) without significant
spin-down. This means that either most of known NSs should be born with
relatively long periods close to presently observed values, or the initial
inclination angles should be large (close to 90) for the magnetodipole model
and very small (close to 0) for the current losses model, or that both models
cannot be applied for the whole evolutionary track of a typical NS. In
particular, magnetar candidates should be born with periods close to the
observed ones within the scope of both models of energy losses. We discuss how
these considerations can influence population synthesis models and age
estimates for different types of isolated NSs. Focusing on the model of current
losses we illustrate our conclusion with evolutionary track reconstructions on
the P--\sin \chi plane. We conclude, that most probably both existing models of
energy losses -- magneto-dipole and longitudinal current -- require serious
modifications, on the other hand, estimates obtained under the standard
assumption of \sin \chi=1=const does not have solid theoretical ground and
should be taken with care.
