Is there an alternative (more robust) operating law/setting for jet-engines? After one engine failed?
Aircrews regularly practice emergency procedures for engine out scenarios in their training and simulations. 

Aircraft manufacturers and airlines provide procedural outlines for various possible emergency conditions specific to the type of aircraft. 

During an in flight emergency, fuel efficiency is not a priority. The aircrew is to ensure safe flight of the aircraft and the priority becomes landing quickly and safely. This may require use of the engine in any fashion to keep the aircraft in flight.

In the report you reference, there is no real way to know what (if anything) caused what appeared to be a trail of smoke seen by another person in another aircraft waiting to take off.