The boost controller has a "scramble" button which overrides the preset boost targets and allows you to run a higher (and unsafe) boost level as long as the button is pressed.
This is useful when you're in the middle of a $10,000 race and you're losing by a few feet.
The "scramble" button I'm talking about is for "boost", which is the amount of positive air pressure inside the intake manifold.
Both "boost" and nitrous can dramatically increase power by essentially getting more oxygen into the combustion chamber, but nitrous is a much more dramatic effect.
This mode is pretty much reserved for go around or post V1 takeoff when one engine on twin engined airliner had failed.
Wow!
Funnily enough I believe the SR-71 has the opposite problem, where the engines would merrily go above Mach 3.5 with no issue but the airframe and everything attached to it would get torn apart by the intense heat if the pilot tried to go any faster
Additionally, there's the Mach Cone. The shock wave off the nose forms a cone shape, with the angle determined by the speed of the aircraft. From the nose to the wingtip forms an angle of about 17.5 degrees, which corresponds well with the max speed from the CIT of Mach 3.3.
That both methods of determining max speed agree shouldn't be surprising. Skunk Works was filled with good engineers.
The airframe, however, will get bent from temperature and you better hope the missile cooling loops don't fail.
The power isn't dialed down at lower speeds in order to provide thrust for maneuvering and climb.