I know very little about the EM145, but there are two common explanations to the name Dutch Roll.
The most common is that it is the motion described by an ice skater on a frozen Dutch Canal.
The less common, but which I prefer, is that it's the motion seen on an old Dutch Merchantman (sailing ship), which were round bottomed with little keel, and thus tended to constantly roll and yaw as they sailed.
G