I thought about it over lunch, and have decided that I think targeting doesn&#x27;t work, in the relevant senses of &quot;targeting&quot; and &quot;works&quot;.<p>There&#x27;s an exception: Targeting geographical areas obviously works. If your market is the city of Toulouse, targeting by geoip gives you most of the intended audience and eliminates almost everyone else, at low cost.<p>The rest of the targeting techniques? Trying to pick male users, trying to pick users over 50 or between 20 and 30, trying to pick people who&#x27;ve visited faucet FAQs in the past? There&#x27;s a long-term strategic cost in user revulsion and there&#x27;s an immediate technical cost in implementing the tracking.<p>I won&#x27;t try to put a number to the cost of creeping out users and making them install adblock, ghostery etc, but it does <i>not</i> seem safe to assume that the cost is smaller than the value of those 20-100% additional clicks.