There are many, many annoying tactics players use to get an edge in the game combat. many rush power weapons, camp with active camo and the sword, or what ever. Personally i like plasma grenades. It's so much fun to half blindly lob one accross the map and by sheer luck stick someone, after ypu know youre going to lose, take them out with you by sticking them, or sprinting toward them after being stuck.
I would say a playey is bad if they can't come out on top without a power weapon that maximizes their distance to their opponents, or can't keeo control of them.