Knowing the maps is overrated.
Frontal charging and engaging the enemy in honorable straight-up combat is the only true way of doing battle!
My K/D on just about any FPS? Around 1, always
(Usually slightly over, I attribute that to the element of surprise which sometimes enables me to kill a group of several people. This of course get's cancelled out by the countless deaths I experience when charging straight up, screaming "FREEDOOOOOOM!" ... hence: K/D of around 1 ^^)