Due to the presence of the shallow resonances in the few-nucleon systems a chiral perturbation theory for the nucleons' scattering amplitudes would be convergent (if at all) at very low energies. That is why Steven Weinberg proposed the theory of ”Nuclear forces from chiral Lagrangians” (Phys.Lett.B 251 (1990) 288), where in contrast to the pion physics the perturbation theory (PT) is developed for the nucleon potentials rather than for the scattering amplitudes. Although these potentials are being calculated nowadays in a rigorous systematic way to the higher than 5-th order of the ChPT, still there is a part of the nuclear studies which is treated in an artisanal (ad hoc) way. This part concerns accounting for the motion of the bound states involved in scattering processes. Meaning of this issue specifically for the chiral effective field theory is discussed in the talk; besides we derive a PT necessary for the ab initio high accuracy nuclear studies which enables one a systematic account for the motion of the bound states involved in scattering processes.