If they had "this is me in private" and "this is me at my job" twitter feeds, I'd buy that; but as long as their bosses use their twitter feeds as a means of corporate promotion (and they use these feeds as a means of self-promotion-in-a-professional-capacity to build an audience which is marketable to their bosses and other potential employers), then really, how "unfiltered and honest" is it? It's just another genre of public professional discourse, and not one I care much for, really.