A Razorback is also a nickname for a turtledeck all the way back to the Rudder ( or at least it is in the circles I have been in ). Vs a blown Canopy, it can reduce drag substantially, especially if the angle is in the 7.5 to 8 degree range, and their is NACA data to support it ( danged if I can find the original ). A Canopy however is preferred if you need a swivel head in a dogfight.
Sorry for the confusion...