[gmx-users] changing atom types versus adding dihedrals to atom types

[Rafael I. Silverman y de la Vega]

Hi all,
in another thread it was recommended that instead of changing the atom
types by analogy to ones with the desired parameter already assigned, that
instead one should assign bonded parameters by analogy.  I was just
wondering how this is better?
 As long as the atom type isnt too different, then why would the torsions
not work out right? If the parameters are interrelated, what makes it
better to add one term to an atom type rather than changing all the terms
(to ones that are supposed to be together)?