An outside review of Bloomberg L.P.’s practices found that a controversial article that compared the damage in an Italian town after a bad deal with JPMorgan Chase to the fallout from the Nazis’ occupation in World War II went “too far.”

The 2011 article, which JPMorgan complained about at the time and Bloomberg declined to change, has long been a sore spot between the bank and Bloomberg and was recently mentioned in a New York Times article that focused on the friction between Wall Street and Bloomberg.

“In one of the great campaigns of World War II, Monte Cassino was completely destroyed in a wave of battles that claimed 75,000 casualties and the lives of hundreds of townspeople. To suggest that a bond deal gone sour, curtailing daycare for 60 children and services for the poor, is comparable to the terror and cataclysm of war is inconsistent with BN’s high standards,” Clark Hoyt, an editor-at-large at Bloomberg News and a former public editor of The Times, found in his review, which focused on the relationship between Bloomberg’s news and commercial operations....