Shields interfere with mobility

As if to confirm Antilles’ pessimism, Dodonna indicated a string of lights on the ever-changing schematic. “Take special note of these emplacements. There’s a heavy concentration of firepower on the latitudinal axes, as well as several dense circum-polar clusters.
“Also, their field generators will probably create a lot of distortion, especially in and around the trench. I figure that maneuverability in that sector will be less than point three.” This produced more murmurs and a few groans from the assembly.

***

Star Wars Trilogy, A New Hope Chapter 11