Knowing the map resonably well, compared to someone that hasn't played it much is an advantage, but it's not a HUGE one. Either way, I hate shock rifle fools, since it's the most abusive weapon ever made. Rocket laucher duels is the only thing that really takes skill, since you can't exactly camp with it.
"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram