Let's say that The Rebel Times has a headline "Member of the Imperial Senate on a diplomatic mission boarded and arrested without cause" while the Empire Daily reports that "Leia Organa, part of the Rebel Alliance and a traitor, taken into custody". Following your process, the "what" is just that Leia was arrested.

Then, the Rebel Times says "Moisture farmer with magic powers joins fight against Empire", but the Empire Daily has "Moisture farmer joins fight against Empire". the common whats are just that a moisture farmer joined the Rebel Alliance, which is true, but much less consequential than if he had magic powers.

Later, the Rebel Times says "Secret Empire super-weapon destroyed at the Battle of Yavin", and the Empire Daily publishes... nothing because they don't want to admit defeat. There's no common information between these stories (because there is no second story), so looking for common whats would conclude that nothing happened.

If the process of analysing the news accounted for the fact that the different outlets are interested in presenting different whats, it could conclude that the fact that the Empire Daily published nothing about the third story doesn't mean that it didn't happen. In the second case, if it could account for the Empire wanting to suppress information about the Force, the conclusion would be that Luke joining the Alliance is somewhat more of a big deal than otherwise. Even in the first case, it might realise that the fact that the two sources don't agree about Leia doesn't mean that one side isn't right.