Utilitarianism and Inequality

Amartya Sen Utilitarianism is perhaps the most commonly used framework of thought for policy making.
From the distant reaches of optimal accumulation to the more mundane exercises of benefit-cost analysis, the additive social welfare function is a common basis for thinking and action. Benefits to different individuals (or groups) are added and the sum compared for selecting optimal plans or projects in theory, and something of that rubs off in practical decision taking as well Is this indeed a good basis for systematic thinking on planning problems ?