  As known, some approximate approaches to the hadron scattering from nuclei
work rather well far beyond the limits of their applicability. This was
explained by cancellation of the contributions (non-adiabatic and off-shell
effects) omitted in these approaches. Moreover, in some cases (in particular,
for the reaction $\bar{p}d \to e^+e^-n$) this cancellation allowed to derive
rather simple analytical formula for the reaction amplitude. Solving the
Faddeev equations, we confirm numerically this formula and, hence, the
cancellations.
