We have a blog discussing products of a variety of manufacturers. Recently a manufacturer asked us if we could
utm tag links from our blog to his site with the tags
Since the manufacturers can already see our traffic in his referral traffic report, I do not see the point of adding
utm tags to all our outbound links to manufacturers but perhaps I am missing an important point.
Is there an advantage of tagging outbound links with
utm tags instead of just leaving the traffic to appear in the referral traffic section of the receiving website (eg is the referrer information in HTTP requests less reliable than