ɐ ɡˈɪvən pˈɛɹ ʌv ɹˈoʊɾeɪmɚz ænd æt pəzˈɪʃənz ænd , ɹᵻspˈɛktɪvli, kænˈɑːt bˈoʊθ biː ɪnðə fˈaɪnəl səlˈuːʃən ɔːlðˈoʊ wˈʌn ɔːɹ ðɪ ˈʌðɚ mˈeɪ biː ɪf ðɛɹ ɪz ɐnˈʌðɚ pˈɛɹ ænd ðæt ˈɔːlweɪz ɡˈɪvz ɐ bˈɛɾɚɹ ˈɛnɚdʒi.
A given pair of rotamers  and  at positions  and , respectively, cannot both be in the final solution (although one or the other may be) if there is another pair  and  that always gives a better energy.