Media Daily News’ Joe Mandese writes about Nielsen making a rule change in the wake of NBC’s “Heroes” ratings maneuver…

One piece a majority of Nielsen clients have decided not to put together is multiple airings of the exact episode of the same broadcast network TV series.

Cable networks cried foul, because Nielsen’s systems currently do not enable them to reprocess ratings the same way. Broadcast networks that have dominant shows airing at the end of the week, also did not like NBC’s decision to exploit the new reprocessing rule to take advantage of a top-rated show - “Heroes” - that airs at the beginning of the TV week on Monday nights.

Ad agency executives didn’t like it because the policy omitted discrete ratings for each episode, making it difficult to conduct apples to apples comparisons on nights and against counter-programming..

Technically, broadcast networks can still do that on rare occasions, but Nielsen’s new policy tightens the loophole so that in such a way that makes it impractical. Basically, any program that meets Nielsen’s standards for being “reportable” has to be reported as an individual telecast. Among the criteria, are that a national TV show reaches at least 30% of U.S. TV households, and carries national TV advertising in it.