  Meson exchange diagrams following from a lagrangian with off-shell
meson-nucleon couplings are compared with those generated from conventional
dynamics. The off-shell interactions can be transformed away with the help of a
nucleon field redefinition. Contributions to to the $NN$- and $3N$-potentials
and nonminimal contact e.m. meson-exchange currents are discussed, mostly for
an important case of scalar meson exchange. (pacs 11.10.Lm, 13.75.Cs, 21.30.-x,
24.10.Jv)
