I would like to agree to that as I am a fan of the holy trinity (tank-heal-dps) and cannot really adapt to the everbody-can-do-anything-concept. But as long as there is only one dps weapon that scales with Focus, Life Staff has to have some dps capabilities.
Otherwise you just deny healers any form of progressing in solo content with adequate damage or always force them to use VG, both of which are not viable options to me.